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New additions for files, fonts, code, audio, and data. Browse every app

Files & Documents: Archives

6 apps

Archive Group Splitter

Split a set of files into separate ZIP downloads. Choose which files belong in each group and keep each file whole.

Batch Text Compressor

Compress several text files to GZIP at once. See how much space each file saves and download all the results together.

GZIP Workbench

Compress a file to GZIP or open a GZIP file. Compare file sizes and download the result without uploading your file.

Password ZIP Packager

Make a password-protected ZIP file on your device. Choose your files and a password, then download the encrypted archive.

ZIP Contents Inspector

See what is inside a ZIP file before you unzip it. Preview text and download the files you choose on your own device.

ZIP Workspace

Edit a ZIP file online. Add files, rename them or remove items, then download a new ZIP without uploading your files.

Files & Documents: Document & Data Services

11 apps

Image Montage Builder

Arrange a ZIP of images into a labeled contact sheet with adjustable columns and spacing.

Legacy Image Format Converter

Convert supported bitmap, TIFF, icon, and legacy raster image files into modern web formats.

Media Conversion Service

Convert an uploaded audio or video file with explicit MP4, WebM, MP3, or WAV output presets.

PDF Attachment Manager

List embedded PDF attachments, extract them into a ZIP, or add a new text attachment to a copy.

PDF Contact Sheet

Turn PDF pages into a numbered thumbnail grid for reviewing and printing a document.

PDF Embedded Asset Extractor

Extract images and supported font files from a PDF. Choose pages and download the files together in a labeled ZIP.

PDF Web Delivery Optimizer

Prepare a PDF for faster page loading in supported viewers. Download a reorganized copy that can load in parts.

PDF Workflow Recipe Builder

Apply several PDF changes in one run. Choose pages, rotate them, edit document details and compress a new copy.

Report Table Digitizer

Turn a table in a text-based PDF report into CSV. Review and edit the cells before downloading the table.

Slide Deck Generator

Make an editable PowerPoint from slide titles and bullet points. Add speaker notes and supported images, then download a PPTX file.

Table Extraction Comparison

Compare two ways to extract PDF tables. Use page borders or aligned text to find cells, then download each result as CSV.

Files & Documents: Document Services

6 apps

Academic Manuscript Exporter

Turn a Markdown manuscript into Word, HTML or EPUB. Keep headings, lists and tables in a file you can read or edit.

Document Format Converter

Queue documents for conversion to DOCX, Markdown, HTML, or EPUB, review each job, and download the results together.

PDF Layout Inspector

Inspect a PDF's page sizes and text positions. See where words are placed and how they are read from the file.

PDF Table Extractor

Extract candidate tables from text-based PDF pages into a CSV report with page and table references.

PowerPoint Content Extractor

Extract slide text, speaker notes, and image references from a PowerPoint deck.

Word Document Style Auditor

Review paragraph styles, headings, table counts, and direct formatting in a Word document.

Files & Documents: Documents & Ebooks

11 apps

DOCX Text Collector

Collect text from Word documents into a searchable reading workspace.

DOCX to Clean HTML

Convert a Word DOCX file to clean HTML. Edit the code, preview the page and download the result on your device.

EPUB Chapter Extractor

Save selected EPUB chapters as HTML files. Choose the chapters you need for your own reading or study.

EPUB Metadata Inspector

Look inside an EPUB ebook. See its title, authors, cover and chapter list without uploading the book.

Parallel Reading Notebook

Read an EPUB beside private passage notes and export your study notebook.

Personal EPUB Reader

Read a local ebook with chapter navigation, adjustable text size, and saved bookmarks.

Spreadsheet Format Converter

Convert supported XLSX, ODS, and CSV data between spreadsheet formats.

Word Document Previewer

Read a DOCX file in a clean browser preview without a desktop editor.

Word Template Layout Checker

Fill a Word template with your own details. Preview the result beside your input and download the completed DOCX file.

Workbook Sheet Splitter

Select worksheets and export each as its own XLSX or CSV file.

XLSX Data Inspector

Inspect workbook sheets, identify blank columns, and export a selected table.

Files & Documents: File Inspection

4 apps

File Checksum Calculator

Calculate a SHA-256 or SHA-512 file hash locally and compare it with an expected checksum.

File Checksum Manifest

Create a SHA-256 or SHA-512 checksum list for several files. Save it to help check later whether the files have changed.

ICC Profile Comparer

Compare two ICC color profiles side by side. Check how their stored color settings and data sections differ.

ICC Profile Inspector

Inspect an ICC color profile. See its version, color space, device type and stored color settings.

Files & Documents: Files & Documents

4 apps

Meeting Minutes Word Exporter

Turn meeting details, agenda items, decisions, and actions into an editable Word document.

PDF CSV Form Filler

Fill a PDF form from CSV rows and download one completed PDF per record.

Spreadsheet Report Builder

Make an Excel report with several sheets. Add tables, clear headings and number totals, then download an XLSX file.

Word Template Builder

Generate a formatted Word letter from a title, recipient, date, and paragraphs.

Files & Documents: Writing & Editing

8 apps

Document Revision Timeline

Replay saved changes to a Quill document. Move between versions and download a copy of the draft at any step.

Documentation Lint Preview

Check how Markdown looks under different rules. Compare previews and find lines that may display differently in another editor.

Markdown Document Printer

Print Markdown or save it as a PDF. Choose the paper size, margins and text style, then preview your document.

Markdown Extension Playground

Try Markdown tables, links and other options. Switch each rule on or off and compare the preview with the HTML.

Newsletter Draft Composer

Write a newsletter with a subject and preview text. Check its phone layout, save a draft and export HTML for your email service.

Rich Text Change Viewer

Compare two Quill Delta documents. Find changed words and formatting, then download the steps that turn one draft into the other.

Rich Text Writing Pad

Write and format notes online. Add headings, lists and links, save drafts in this browser and download a copy.

Web Clipping Formatter

Turn pasted article HTML into a clean Markdown note. Keep the title, author, source link and your own comments together.

Images & Design: 3D Mesh Processing

2 apps

3D Mesh Health Checker

Check a 3D mesh for holes and other shape issues. See its size, triangle count and surface measurements.

Mesh Format Converter

Convert a triangle mesh between STL, PLY, and OBJ with a geometry summary.

Images & Design: Diagram Editors

2 apps

Diagram Format Workspace

Open and edit Draw.io XML files or editable SVG and PNG diagrams. Keep a project copy or export an image to share.

Embedded Diagram Desk

Make diagrams with shapes, arrows, pages and layers. Edit in a Draw.io workspace and save a copy to your device.

Images & Design: Diagrams & Graphs

1 app

Flowchart Editor

Make a flowchart with steps, decisions and arrows. Drag shapes into place, label connections and save an editable diagram.

Images & Design: Document & Data Services

1 app

Font Subset Service

Create a smaller font containing the characters needed for a specific page or design.

Images & Design: Drawing & Wireframes

2 apps

Lightweight Whiteboard

Draw shapes, arrows and freehand ideas on a clean local whiteboard with editable text, image attachments, grouping and reusable project files.

Wireframe Sketch Kit

Sketch product screens with reusable cards, navigation, buttons, forms and device layouts, then save an editable project or export an image.

Images & Design: Fonts & Vectors

5 apps

Font Character Coverage Checker

Check whether a font has every character in your text. Find missing letters and symbols before using it in a design.

Font File Inspector

Inspect a TTF, OTF or WOFF font file. See its name, style, character coverage and other font details.

SVG Cleanup Comparer

Compare original SVG markup with an optimized version and inspect the exact lines that changed.

SVG Optimizer

Reduce SVG markup, remove redundant data, and download a lighter vector file with a visual preview.

Text to SVG Outlines

Use your own font to turn a line of text into downloadable SVG paths.

Images & Design: Layout & Design

1 app

Responsive Layout Sketcher

Sketch a clean grid for phone, tablet and desktop. Arrange each breakpoint independently, preview any width and export usable HTML and CSS.

Text & Writing: Language & Analysis

4 apps

Language Detector

Find the likely language of a piece of text. Compare possible matches and see which results need a closer look.

Multilingual CSV Sorter

Sort CSV rows by language. Check the suggested language for each row, fix mistakes and download a file for each language.

Reading Vocabulary Profiler

Compare the words in two texts. Count each word, find words they share and see each match in the original text.

Text Analytics Desk

Count words and sentences in English text. Explore parts of speech, dates and other details, then download the results.

Text & Writing: Language Experiments

2 apps

Document Similarity Finder

Compare the words in up to 60 short documents. Rank similar pairs, see what they share and download every comparison.

Text Classification Sandbox

Teach a small model to label text using your examples. Check it on separate test text and download the predictions and results.

Text & Writing: Speaking & Presenting

1 app

Speech Teleprompter

Read a scrolling script while you practise a speech or record a video. Adjust the speed, font size and mirror direction on a light reading screen.

Text & Writing: Studying & Practice

1 app

Practice Test Mistake Notebook

Turn missed practice questions into a personal learning notebook. Save your incorrect answer, the explanation, and a date to try again.

Text & Writing: Work & Job Hunting

1 app

Interview Answer Notebook

Build a personal bank of interview questions and prepared answers. Organize by skill and link questions to upcoming interview stages.

Video & Audio: Audio Analysis

2 apps

Audio Spectrogram Lab

See the frequencies in an audio file over time. Compare spectrogram settings and download charts for closer study.

Music Tempo & Beat Explorer

Estimate a recording's tempo in beats per minute. Check beat marks on its waveform and download their times.

Video & Audio: Music & Sound

16 apps

ABC Notation Editor

Write ABC music notation and see the score. Listen to the tune and download ABC, SVG or MIDI files.

Ambient Sound Mixer

Mix your own sound loops. Set each volume, choose which clips repeat and use a sleep timer to stop playback.

Audio Clip Marker

Mark clips on an audio waveform. Set exact start and end times, listen to each section and save the timestamps.

Audio Feature Explorer

Explore changes in an audio recording. See charts of sound level and frequency features, then download the measured values.

Folk Tune Transposer

Transpose an ABC folk tune to a new key. Preview the score, listen to the result and download the rewritten tune.

Interval Ear Trainer

Practise hearing the distance between two notes. Choose your musical intervals, listen and check your answers.

Live Audio Effects Playground

Try live effects on an audio file. Adjust volume, filters, left-right balance and echo while listening to the result.

MIDI Piano-Roll Inspector

Open a MIDI file and see its notes on a piano roll. Explore tracks and tempo changes, listen and export note data.

MIDI Transposer

Move MIDI notes up or down in pitch. Choose tracks and note ranges while keeping timing and other MIDI events.

Podcast Chapter Editor

Add chapters to a podcast while you listen. Name each chapter, adjust its time and download the chapter list.

Rhythm Reading Trainer

Practise reading and tapping musical rhythms. Listen to a pattern, tap along and see how close your timing was.

Scale & Chord Finder

Find notes and chords in major and minor scales. See them on a keyboard and listen to each scale or chord.

Sheet Music Snippet Maker

Make a short piece of sheet music from notes and durations. Choose the clef, time signature and tempo, then save the score.

Soundboard Builder

Make a soundboard from your own audio clips. Name each pad, set volumes and play sounds with buttons or keyboard shortcuts.

Stereo Channel Tester

Test your left and right audio channels. Play a tone, adjust its pitch and run an automatic channel check.

Timbre Comparison Tool

Compare the tone and sound level of two recordings. View matching charts and download their measured differences.

Video & Audio: Music Practice

2 apps

Microphone Instrument Tuner

Tune a single instrument note using your microphone. See the nearest note, frequency and cents sharp or flat with standard A4 = 440 Hz tuning.

Music Practice Metronome

Practise with a steady beat from 30 to 240 BPM. Choose quarter, eighth or sixteenth notes, adjust the volume, and follow the visual beat markers.

Video & Audio: Subtitles

4 apps

SRT ↔ VTT Converter

Convert subtitle timestamps between SubRip and WebVTT and download the new subtitle file.

Subtitle Language Worksheet

Turn subtitles into a study worksheet with timestamps, original lines, and space for your translation.

Subtitle Overlap Checker

Find overlapping subtitle cues and short gaps in an SRT or WebVTT file.

Subtitle Reading Speed Checker

Measure characters per second for every subtitle cue and find lines that may be too fast to read.

Data & Calculators: Charts & Data

15 apps

Chart Specification Playground

Edit a Vega-Lite chart in JSON. Preview changes, check errors and download the chart as SVG or its settings as JSON.

Custom Infographic Builder

Make an infographic from CSV data. Choose bars, dots or number cards, edit the artwork and download SVG or PNG images.

Data Quality Visualizer

Check CSV data for missing values, duplicate rows and unusual numbers. Explore charts and download a column report.

Data Story Slide Builder

Turn data into a slide presentation. Add charts and notes, arrange slides and download a presentation that opens in a browser.

Declarative Chart Builder

Build a Vega-Lite chart from CSV data. Choose columns, chart marks and summaries, then save the chart and its settings.

Function Graphing Pad

Plot up to six math functions together. Change values and graph ranges, zoom in and download the chart.

Hierarchical Data Explorer

Show nested JSON as a treemap, sunburst or icicle chart. Open each branch to explore its values and save an image.

Interactive Chart Studio

Make bar, line, scatter, pie and other charts from CSV data. Choose columns, group values and save your chart project.

Measured Data Surface Viewer

Turn x, y and z measurements into a 3D surface. Rotate the view, add contour lines and download the chart.

Personal History Timeline

Make a timeline of personal events. Add dates, groups and notes, then search your history and save an editable copy.

Personal Progress Dashboard

Track reading, habits and projects with charts. Add entries, set targets and save a copy of your dashboard.

Project Milestone Viewer

See project milestones on a timeline. Add dates and notes, group related work and focus on a chosen date range.

Sensor Comparison Dashboard

Compare sensor readings on shared or separate charts. Pick a time range and review missing values and number summaries.

Small Multiples Explorer

Compare groups of data in matching charts. Use histograms, box plots or violin plots with the same number scale.

Time-Series Log Viewer

Plot timestamped CSV measurements over time. Zoom into a range, spot gaps and download a summary of the selected data.

Data & Calculators: Cooking & Baking

1 app

Pizza Dough Calculator

Calculate flour, water, salt and yeast for homemade pizza. Choose your dough-ball count, weight and hydration, then save or print your recipe.

Data & Calculators: Data File Services

1 app

Parquet Explorer

Open a Parquet file and explore its rows and columns. Filter or group rows, preview the results and download a data report.

Data & Calculators: Diagrams & Graphs

13 apps

Automatic Flow Layout

Arrange connected shapes into a clear flow. Choose a direction and spacing, adjust positions and download the diagram.

Community Structure Explorer

Find groups of closely connected nodes in a network. Adjust the grouping settings and download each node's group.

Complex Diagram Arranger

Rearrange a busy diagram automatically. Try rows, circles, trees and other layouts, then edit and save the result.

Decision Tree Builder

Build a decision tree with questions and answers. Check its branches, follow a path and download the project.

Dependency Map Builder

Turn a CSV list of dependencies into a diagram. Edit connections, labels and positions, then save the map or project.

Game Map Route Planner

Plan a route through your game map. Set travel costs, block locations and download a diagram of the chosen path.

Graphviz DOT Playground

Preview Graphviz DOT diagrams online. Choose a layout, check syntax errors and download the graph as an SVG.

Knowledge Map Editor

Build a map of ideas and how they connect. Add notes and tags, search your map and save a project file.

Network Centrality Calculator

Find well-connected nodes in a network. Compare degree, PageRank, betweenness and closeness scores, then download the results.

Network Layout Comparison Lab

Compare layouts for the same network side by side. Choose the clearest view and keep it for editing or download.

Org Chart Layout Helper

Make an organization chart from reporting relationships. Check for errors, arrange people and export the diagram.

Relationship Graph Explorer

Explore a map of items and their connections. Search names and tags, read notes and focus on nearby links.

Shortest Path Teaching Tool

Find the shortest route through a network. Compare the fewest steps with the lowest cost and see how the route is chosen.

Data & Calculators: Document & Data Services

11 apps

CSV Transformation Service

Select, filter and clean CSV columns with a recipe. The service processes rows in small groups and returns a new CSV.

Data Cleaning Studio

Clean a CSV table with repeatable steps. Rename columns, fix values and filter rows, then download the cleaned table.

Data Pipeline Previewer

See what each step in a CSV data pipeline changes. Review row counts and sample values before saving the final table.

Dimensionality Reduction Explorer

Turn many number columns into a 2D PCA chart. Explore patterns and see how much of the data's variation the chart keeps.

Geometry Repair Workbench

Check GeoJSON shapes for errors such as crossing polygon edges. Try repairs and compare the results before using the new file.

GIS Table Join Desk

Add CSV data to a GeoJSON map by matching a shared field. Check which records matched and download the combined file.

Linear Optimization Workbench

Solve a linear optimization problem with limits on its variables. See the best result and check how each constraint is met.

Math Expression Code Generator

Turn a math expression into C, JavaScript or Python code. Name the variables and copy or download the result.

Spatial Dataset Cleanup

Clean a GeoJSON dataset and change its coordinate system. Review shape errors, attempt repairs and download a new copy.

Symbolic Equation Solver

Solve a supported equation with one unknown. Find exact roots when possible and compare their decimal values.

Tabular Model Training Lab

Train simple models from number columns in a CSV file. Test them on separate rows and compare their scores.

Data & Calculators: Kitchen & Groceries

1 app

Unit-Price Shopping Comparison

Compare grocery pack sizes by price per kilogram, litre or item. Enter final prices and quantities to find the lowest unit price.

Data & Calculators: Local SQL

5 apps

CSV SQL Workbench

Run SQL queries on CSV files in your browser. Check column types, combine tables and download your results.

JSON SQL Query Tool

Query JSON data with SQL on your device. Explore tables and nested values, then download the results.

SQL Practice Sandbox

Learn SQL with a working sample database, eight guided exercises, hints, checked results and reusable query notebooks.

SQLite File Explorer

Open a SQLite database on your device. Browse tables, inspect their links and download query results without uploading the file.

Table Join Builder

Join CSV or JSON tables by matching columns. Preview the SQL, choose how to keep unmatched rows and download the combined data.

Data & Calculators: Maps & GIS

14 apps

Coordinate System Converter

Convert map coordinates between WGS84, Web Mercator, UTM and Canada Lambert. Check the converted points on a map.

Encoded Route Decoder

Decode an encoded polyline into map coordinates. Preview the route and download its longitude and latitude values.

Freehand Stroke Optimizer

Simplify a freehand drawing with fewer points. Compare detail levels and save a smaller SVG or editable project.

Geographic Measurement Desk

Measure routes and areas on a map. Draw or import shapes, find their centers and create a boundary around them.

GeoJSON to Shapefile Exporter

Convert GeoJSON to shapefile downloads. Keep map shapes and their data together with the files needed to open them.

GIS Attribute Export Assistant

Choose which map shapes and data fields to export. Download a smaller GIS dataset or a shapefile package.

GPX to GeoJSON Converter

Turn GPX tracks, routes and waypoints into GeoJSON and inspect their names, coordinates and properties.

KML to GeoJSON Converter

Convert local KML placemarks and geometry into editable GeoJSON with a map and attribute preview.

Personal Places Map

Pin meaningful places, edit coordinates and notes, organize categories and save a portable map dataset.

Photo Travel Map

Map GPS-tagged photos locally, inspect their locations and place photos without location tags by hand.

Route URL Packer

Turn route coordinates into a short encoded polyline. Preview the route and copy the text for use in mapping tools.

Shapefile Previewer

Open a local shapefile ZIP, choose a layer and inspect its map geometry, coordinate system and attribute records.

Shapefile to GeoJSON Converter

Convert supported shapefile archives into WGS84 GeoJSON while preserving geometry and decoded attributes.

Survey Coordinate Checker

Check whether two sets of map coordinates describe the same places. Measure the gaps and flag points beyond your chosen limit.

Data & Calculators: Numbers & Reports

2 apps

Localized Report Formatter

Format numbers and prices in a CSV or JSON table for different regions. Check errors and download your finished report.

Number Formatting Playground

See how numbers, prices and percentages look in different languages and regions. Compare formats without changing the values.

Data & Calculators: Personal Notebooks

4 apps

Offline Inventory Notebook

Keep belongings, quantities, photo previews and locations in a searchable local notebook, with complete backups and CSV import.

Offline Recipe Notebook

Save recipes with ingredient lists, ordered steps and photos. Search locally, scale quantities and export a clean printable recipe.

Personal Snippet Vault

Keep reusable text and code snippets in searchable categories, with tags, favorites, exact-text copying and portable exports.

Reading & Watchlist Tracker

Keep books, films, series and courses together. Track progress, ratings, dates and notes in a private, searchable local collection.

Data & Calculators: Planning & Productivity

6 apps

Dashboard Layout Exporter

Design a dashboard grid and export its layout as JSON. Arrange widgets and save their types, positions and sizes.

Lightweight Project Planner

Turn tasks, dates and dependencies into an editable project timeline, with milestones, progress and portable backups.

Personal Dashboard Arranger

Make a calm dashboard of clocks, notes, metrics and small data tables. Arrange every widget and keep an editable local backup.

Personal Kanban Board

Give every task a place. Move cards between columns, add checklists and keep your board on your device.

Renovation Timeline Planner

Lay out renovation phases, trades and milestones in one clear, printable timeline.

Study Dashboard Builder

Give your study day a little structure. Arrange focus timers, notes and assignment panels in a private, saved workspace.

Data & Calculators: Scientific Data

3 apps

Graph Algorithm Workbench

Explore a network's connections and groups. Count links and find the path with the fewest steps between two nodes.

Signal Filter Designer

Design a digital Butterworth filter. Choose frequencies to keep or reduce, preview its response and download the filter settings.

Time-Series Resampler

Group timestamped CSV measurements by hour, day, week or month. Choose how to summarize the values and download the result.

Data & Calculators: Scientific File Services

3 apps

Chemical File Converter

Convert chemical structures between SDF, MOL and SMILES. Preview molecules, check errors and download the converted files.

GeoTIFF Inspector

Look inside a GeoTIFF map image. See its image bands, map coordinates and sample values, with an adjustable preview.

Raster Crop Service

Crop a GeoTIFF to a rectangle or polygon. Keep the map's coordinate grid and download the cropped image.

Data & Calculators: Tables & Data

2 apps

Editable Data Table

Open CSV or JSON as an editable table. Keep exact text, change individual cell types, filter rows and save your work privately.

Record Review Queue

Review a table row by row, flag problems, attach notes and export accepted, rejected and pending records without uploading your data.

Data & Calculators: Time & Calendars

6 apps

Calendar Conflict Finder

Find overlapping events in an ICS calendar. Choose event series and see when each clash starts and how long it lasts.

Community Event Calendar

Keep a clear calendar of local events, with categories, locations, search and a portable agenda to share.

Course Schedule Exporter

Turn weekly classes, term dates and skipped days into a time-zone-aware calendar you can import anywhere.

Daylight-Saving Transition Explorer

See when clocks change in a time zone. Find skipped or repeated times and compare each local time with UTC.

Recurring Schedule Debugger

Check which dates a calendar repeat rule creates. Find skipped dates and see how time zones and clock changes affect the schedule.

Weekly Time-Block Planner

Make room for your tasks in a weekly calendar. Drag, resize, edit and save your plan on your device.

Data & Calculators: Work & Job Hunting

1 app

Job-Search Progress Dashboard

Review daily applications, current pipeline statuses, recorded stage outcomes and upcoming follow-ups from your saved job-search records.

Developer Tools: Architecture & Documentation

1 app

Architecture Documentation Builder

Make a system architecture document with Mermaid diagrams and notes. Download one HTML guide or a bundle of diagrams.

Developer Tools: Code & Configuration

8 apps

HTML to Markdown Converter

Turn HTML headings, links, lists, and emphasis into readable Markdown for your notes or documentation.

JSON5 to JSON Converter

Turn commented JSON5 with trailing commas and unquoted keys into strict, formatted JSON.

SQL Formatter

Make SQL easier to read with consistent indentation and keyword casing. Choose the dialect your database uses.

SQL Query Comparer

Format two SQL queries consistently, then see which lines were added, removed, or kept.

TOML ↔ JSON Converter

Convert TOML configuration to JSON and convert JSON objects back to TOML.

TOML Config Validator

Check TOML syntax, find parsing errors, and inspect the values behind each configuration key.

YAML ↔ JSON Converter

Convert YAML to readable JSON, or turn JSON into clean YAML. Check nested data without uploading a file.

YAML Tree Inspector

Explore YAML paths, value types, and nested settings in one readable table.

Developer Tools: Code & Validation

17 apps

Code Formatter Desk

Format JavaScript, TypeScript, JSON, CSS, HTML, Markdown or YAML. Choose spacing and style, then review the changes.

Code Snippet Image Maker

Turn code into a clear SVG or PNG image. Choose colors, add a title and show line numbers for sharing or teaching.

Code Token Inspector

Explore how a code highlighter labels words and symbols. See which parts are keywords, strings, comments and other code types.

Configuration Comment Editor

Edit a JSON5 file with comments. Check its values and download standard JSON for apps that do not accept comments.

CSV Field Validator

Apply named validation rules to CSV columns and download a row-by-row error report.

Custom Code Highlighter Builder

Choose your own code highlight colors. Preview the theme and download its CSS and a sample HTML code card.

Data Contract Tester

Check a batch of JSON records against the same rules. Download a report showing which records and fields need fixing.

Embeddable Code Card Maker

Make a colorful code card for a web page. Download one HTML file with its styles included and no extra files to load.

Formatting Rule Demonstrator

See how code formatting rules change your code. Compare the original and formatted versions line by line.

Input Validation Playground

Check sample emails, URLs, identifiers, dates, and numbers against visible validation rules.

JSON Difference Explorer

Compare two JSON files and find what changed. Open each difference to see added, removed and edited values.

JSON Schema Validator

Check JSON against a JSON Schema. Find missing fields, wrong value types and other errors with their exact locations.

Language Detection Preview

Guess the programming language of a code snippet. Compare the top two matches and check the highlighted result.

Regex Capture Group Reference

Find named and numbered capture groups in a regular expression. See where each group starts and how it is used.

Regular Expression AST Explorer

See how a JavaScript regular expression is built. Explore its parts in a tree and find syntax errors without running the pattern.

SQL Style Comparison

Compare three ways to format the same SQL query. Try different spacing and keyword styles, then download each version.

Syntax Theme Comparator

Compare three color themes for the same code. Preview how keywords, text and comments look before choosing a style.

Developer Tools: CSS & JavaScript

8 apps

CSS Declaration Explorer

Search CSS property names and values, find important declarations, and export their locations for stylesheet cleanup.

CSS Prefix Preview

Add vendor prefixes for browsers you choose. See resolved browser versions and download the resulting CSS and source map.

CSS Rule Inventory

Count CSS rules, selectors, properties, and at-rules. See repeated values and download a complete stylesheet inventory.

CSS Syntax Validator

Check CSS syntax, find errors by line and column, and explore a structured tree without applying the styles to your page.

CSS Transformation Playground

Flatten nested CSS, add browser prefixes, and remove comments with a before-and-after view and downloadable CSS.

JavaScript Minifier

Make JavaScript smaller with controls for compression, variable names, and comments. Download the code and an optional source map.

Legacy CSS Compatibility Diff

Compare CSS before and after browser-prefix changes. Inspect added and removed declarations for your chosen browser targets.

Minification Impact Viewer

Compare original, minified, and formatted JavaScript. Measure UTF-8 and gzip sizes, then download code and source maps.

Developer Tools: Developer Utilities

9 apps

Barcode Check Digit Calculator

Calculate or verify the GS1 check digit for GTIN-8, UPC-A, EAN-13, GTIN-14, and SSCC-18 codes.

Barcode CSV Auditor

Check a CSV column of product barcodes for invalid lengths, non-digit characters, and incorrect check digits.

Domain Character Inspector

Check the exact characters in a domain name. See Unicode codes and decoded Punycode to spot lookalike letters.

Glob Pattern Tester

Test a file glob against a list of paths. See which filenames match your pattern before using it in a script.

HTML Entity Decoder

Decode named and numeric HTML entities into plain text without rendering the result as HTML.

HTML Entity Encoder

Convert text to HTML entities. Escape symbols such as < and & so they can appear as text in HTML code.

IDN / Punycode Converter

Convert international domain names between Unicode and Punycode. Compare readable names with their xn-- form.

Semantic Version Range Checker

Check which package versions fit an npm version range. Test rules such as ^1.2.3 against a list of versions.

Unicode Entity Explorer

Inspect Unicode characters one by one. See each character's number, UTF-8 bytes and HTML entity code.

Developer Tools: Document & Data Services

2 apps

API Response Reshaper

Reshape a JSON API response with jq. Save the input, query and result together so you can repeat the same steps later.

Archive Text Search

Search text inside a ZIP file. Choose a file pattern and search rule, then download matching lines with their filenames.

Developer Tools: IDs & Codes

3 apps

Random Invite Code Batcher

Create unique offline invitation codes with a readable alphabet and optional event prefix, then download the full batch.

Record ID Migration Mapper

Map old record IDs to fresh UUID v4 or v7 values, review repeated IDs, and export a complete local lookup table.

Short Identifier Generator

Generate random short IDs using your chosen alphabet, length and prefix, then export a batch as CSV, JSON or text.

Developer Tools: Queries & Dependencies

3 apps

Dependency Order Analyzer

Find a workable order for tasks that depend on each other. Check for loops that make the task order impossible.

jq JSON Query

Run a jq filter against JSON and download the transformed result.

Log Search Workspace

Search several log files with a regular expression and export matching lines with filenames and line numbers.

Productivity: Cars & Vehicles

8 apps

Car Ownership Cost Tracker

Combine logged fuel, servicing and other vehicle expenses. Compare categories and months, then export a dated ownership-cost report.

Fuel Fill-Up Diary

Log fuel purchases and track fuel consumption across repeated fill-ups. Handle partial tanks, missed entries and metric or imperial units.

Mileage-Based Service Reminders

Plan vehicle maintenance using dates, odometer readings or both. Track due targets, completion history and recurring intervals.

Repair Quote Versus Actual Tracker

Track repair estimates alongside final invoices. Keep the original quote, record completed work and see cost differences.

Used-Car Service History Pack

Prepare a selected vehicle maintenance history for sharing. Choose records, optional private fields and individual receipt attachments.

Vehicle Document Expiry Calendar

Organize vehicle registration, inspection and insurance dates with attached documents. Review upcoming targets and export calendar entries.

Vehicle Parts Inventory

Track spare parts and consumables for each vehicle. Record part numbers, suppliers, fractional quantities and usage history.

Vehicle Service History Organizer

Keep vehicle repairs, servicing, receipts and odometer readings together. Search your history and save browser-local backups.

Productivity: Collections & Belongings

1 app

Collectibles Condition & Value Diary

Keep photos, condition records, acquisition costs and your own dated value estimates for a collection. Find items by collection or tag and export selected records.

Productivity: Cooking & Baking

2 apps

Baker’s Percentage Recipe Builder

Build and save bread formulas with flour at 100%. Add ingredient percentages, scale from flour weight or total portions and keep your recipe steps together.

Bread Fermentation Schedule

Turn your bread recipe into a timed baking checklist. Choose a saved formula, set a start time and plan mixing, fermentation, proofing, baking and cooling.

Productivity: Family & Care

5 apps

Baby Feeding Diary

Record feeds with start and end times, feeding method, optional amounts and caregiver names. Keep an editable diary and daily totals in this browser.

Baby Sleep Log

Log sleep and naps with saved timers or manual start and end times. Review daily sleep totals, including sleep that crosses midnight.

Baby Tummy-Time Log

Record tummy-time sessions with a timer or manual times. Keep observations, caregiver labels and daily recorded durations together.

Caregiver Handover Summary

Prepare a printable handover from recorded feeds, sleep, nappy changes and tummy time. Choose a child, date range and private fields to include.

Nappy Change Tracker

Keep a dated nappy-change diary with wet and solid labels, optional colour and notes. See the latest recorded change and daily counts.

Productivity: Gardening & Plants

5 apps

Plant Care History

Keep watering, fertilising, repotting, treatments and observations in one dated plant journal. Correct older entries and export the history you need.

Plant Collection QR Labels

Create printable plant labels that open saved care instructions when scanned. Choose the label text and optional location, then download a QR image or print sheet.

Plant Growth Photo Diary

Compare dated photos of a plant as it grows. Keep captions, notes and optional height measurements alongside a browser-local image gallery.

Plant Watering Queue

Keep plant watering checks organized by date and location. Record watering, pause schedules and see the next check update from your care history.

Plant-Sitter Care Sheet

Prepare a clear handover for someone looking after your plants. Select plants, care instructions and optional details, then download a printable sheet.

Productivity: Home & Household

4 apps

Borrowed Belongings Tracker

Remember who borrowed your belongings and when they should return. Keep active loans, record returns and download expected return dates.

Donation and Decluttering Tracker

Give possessions a next step: keep, donate, sell or lend. Organize items by location and record when donations or sales leave your household.

Household Battery Replacement Log

Record battery replacements and recharges for household devices. Keep battery types, change history and optional planned intervals in one place.

Personal Product Shortlist

Compare purchase candidates using your own criteria, prices, product links and notes. Group similar options and mark your chosen products.

Productivity: Kitchen & Groceries

8 apps

Cook With What I Have

Find which of your saved recipes you can cook with the ingredients in your pantry. Scale servings, check missing amounts and record meals as cooked.

Food Waste Diary

Log discarded food, quantities and reasons while updating pantry stock. Review waste over a date range and estimate its recorded purchase cost.

Freezer Stock Planner

Organize frozen food by drawer or shelf, track portions and reserve batches for upcoming meals. Keep an editable freezer inventory in your browser.

Grocery Price History

Compare prices you have paid for the same grocery product over time. Normalize package sizes and download your purchase history.

Low-Stock Grocery Reminders

Turn minimum pantry stock levels into a grocery list. See what to buy as you record purchases, cooking and food waste.

Opened-Food Reminder

Record when food packages were opened and track your chosen after-opening intervals. Keep partial packages separate and download date reminders.

Pantry Expiry Tracker

Keep pantry, fridge and freezer food dates in one place. See batches due soon, filter your stock and download calendar reminders.

Recipe Cost Per Serving

Calculate the ingredient cost of homemade meals from your purchase records. Scale recipes, compare cost per serving and see which prices are missing.

Productivity: Knitting & Crafts

4 apps

Knitting Increase and Decrease Planner

Spread increases or decreases across one knitting row. See exact stitch groups and save the plan with your project.

Knitting Project Progress Organizer

Keep planned, active and finished knitting projects connected to patterns, notes, counters and allocated yarn. Save a local project archive.

Knitting Row Counter

Keep row counts, named counters, notes and checkpoints with each knitting project. Pick up where you left off in this browser.

Yarn Stash Matcher

Compare your project’s yarn requirements with recorded stock, colours and dye lots. See available length and shortages by batch.

Productivity: Personal Productivity

6 apps

Daily Habit Grid

Track daily habits with a twelve-week activity grid. Record counts, correct past days and see active-day streaks without losing your history.

Focused Text Reader

Read a passage one word at a time with an anchored focus letter. Adjust the pace, move between sentences and resume from your saved position.

Private Bookmark Library

Keep useful links in a searchable library. Add tags and notes, import browser bookmarks and export a portable copy, all on your device.

Private Notes & Tasks

Capture ideas, pin important notes and check off small tasks. Organize by label, search your notebook and export your writing as Markdown.

Project Timer & Timesheet

Track time by project, pause for breaks and save a timesheet. Add past sessions, filter by date or project and download your recorded hours.

Timestamped Meeting Notes

Keep named meeting sessions with timestamped notes, speakers and decisions. Search a meeting and export its discussion as a Markdown timeline.

Productivity: Studying & Learning

2 apps

Exam Flashcard Workload Planner

Estimate flashcard reviews before an exam. Choose study days, a daily new-card limit and a time budget, then download the daily workload plan.

Spaced Repetition Flashcard Trainer

Study your own flashcards with review times that adapt to your answers. Reveal each answer, rate your recall and return when cards are due.

Productivity: Work & Job Hunting

3 apps

Job Application Tracker

Track applications, interviews and outcomes in a clear local workspace. Keep posting details, submission dates, skill tags and next actions together.

Job Offer Comparison Worksheet

Compare saved offers across annual cash pay, benefits, commute, flexibility and your own weighted priorities. Keep unknown amounts visible.

Recruiter Follow-Up Organizer

Keep recruiter contacts, conversation notes and follow-up tasks beside your applications. Track due dates and download a calendar.

Learning & Reference: Astronomy & Satellites

4 apps

Eclipse & Conjunction Calendar

Make an astronomy calendar of eclipses, Moon phases and planetary alignments. Search events and check their dates.

Planet Visibility Explorer

Find when planets are above your horizon. Compare rise and set times, sky positions and dark hours for your location.

Satellite Orbit Viewer

Plot satellite orbits from your own TLE data. Follow ground tracks and compare height, speed and viewing angles over time.

Satellite Pass Planner

Find satellite passes above your location using TLE data. See sky paths and estimated light conditions at each peak.

Learning & Reference: Astronomy Services

2 apps

Ephemeris Comparison Desk

Compare Sun, Moon and planet positions from two JPL models. Chart their differences and download the positions for your chosen time.

Observing Night Planner

Plan a night of stargazing. Compare target heights, dark hours and distance from the Moon, then export your observing windows.

Learning & Reference: Biological Sequences

2 apps

Sequence Alignment Viewer

Compare two short DNA sequences. Line up their bases and inspect matches, differences and gaps.

Sequence Format Converter

Convert biological sequence files between supported formats. Choose input and output formats and download the new file.

Learning & Reference: Language & Calendars

7 apps

Braille Byte Decoder

Decode text from eight-dot braille byte patterns. Restore text made with a matching byte encoder; this is not a braille translator.

Braille Byte Encoder

Encode text bytes as eight-dot Unicode braille patterns. This reversible code is not a translation into readable braille.

Braille Dot Cell Explorer

Explore the eight dots of a Unicode braille cell. Choose raised dots and see the matching character and byte value.

Nepali Calendar Maker

Make a month of Nepali BS dates with corresponding Gregorian dates and weekdays.

Nepali Date Converter

Convert a calendar date between Gregorian AD and Nepali Bikram Sambat BS, with English and Nepali output.

Phonetic Spelling Helper

Spell names, reference numbers, and short messages with the NATO phonetic alphabet.

Radio Spelling Practice

Practise NATO phonetic code words with a scored quiz, immediate feedback, and downloadable results.

Learning & Reference: Math & Science

18 apps

AC Impedance Teaching Lab

Explore how resistors, coils and capacitors affect an AC circuit. Compare series and parallel circuits at a chosen frequency.

Calculus Expression Helper

Find a derivative or integral of a supported expression. Compare the formulas and check the result at a chosen value.

Complex Number Workbench

Calculate with complex numbers such as 3 + 4i. See the answer on a graph and compare its distance and angle.

Descriptive Statistics Desk

Summarize number columns in a CSV file. See averages, ranges, missing values and a chart of how the values are spread.

Fraction Worksheet Checker

Check fraction sums and answers. See common-denominator steps and simplified fractions for each line of your worksheet.

Linear Systems Workbench

Solve a system of linear equations in the form Ax = b. See the solution and how closely it fits each equation.

Matrix Laboratory

Multiply, transpose or invert matrices. Check their size and see warnings when a calculation may be unstable.

Polynomial Exploration Desk

Expand and factor polynomials. Find a derivative and calculate the value of an expression at a point you choose.

Precision Decimal Calculator

Calculate with long decimal numbers. Choose the precision and compare the answer with a standard computer calculation.

Probability Distribution Explorer

Explore probability distributions with charts. Change the settings and see how the curve and chances change.

Recipe Fraction Scaler

Scale a recipe up or down with exact fractions. Keep each ingredient and unit beside its new amount.

Rounding Method Demonstrator

Compare nine ways to round numbers. See what happens with negative numbers and values exactly halfway between two choices.

Scientific Calculator Notebook

Solve calculations in a reusable notebook. Name values, use units and matrices, and use earlier answers in later lines.

Statistical Test Workbench

Run a t-test to compare averages. Choose one sample, paired measurements or two groups, then review the results and assumptions.

Symbolic Algebra Workbench

Simplify, expand or factor an algebra expression. Compare the new form with the original and check a sample value.

Symbolic Computation Worksheet

Work through several algebra or calculus steps in order. Review each result and download the full worksheet.

Tangent-line Visualizer

Draw a function and its tangent line. Move a point along the curve to see how the slope and line equation change.

Unit-aware Formula Calculator

Make a formula with named inputs and units. Change the measurements, calculate again and save the formula for later.

Learning & Reference: Routes & Geography

3 apps

GPX Metadata Inspector

Inspect tracks, points and times in a GPX file. Check recorded heights and approximate distance without uploading your route.

GPX Segment Exporter

Extract one recorded track segment from a GPX file and save it as a new GPX document.

GPX Waypoint Exporter

Extract GPX waypoints into a CSV with names, coordinates, elevations, and timestamps.

Learning & Reference: Scientific File Services

2 apps

Astronomical Coordinate Converter

Convert sky coordinates between equatorial, Galactic and ecliptic systems. Choose the reference settings and download the new coordinates.

FITS File Explorer

Open a FITS astronomy file. Read its headers, preview image data and download selected table rows with a report.

Games & Play: Chess

2 apps

Chess Position Inspector

Explore a chess position on an interactive board, play legal moves, browse the game, and export FEN or PGN.

PGN Game Inspector

Browse a chess game on a board, add notes to individual positions, and export an annotated PGN.

Games & Play: Game Nights

4 apps

Board-Game Group Performance Report

Compare saved board-game results by game and scoring system. See games played, solo and tied wins, win rates and average scores for your group.

Board-Game Night History

Keep completed game nights with players, round scores and winners. Filter your history, inspect past sessions and download records.

Board-Game Scorekeeper

Track board-game players, round scores and running totals. Choose high-score or low-score rules, correct earlier rounds and save the finished game.

Darts Scorekeeper

Keep darts scores for 301, 501, 701 or 1001. Record individual throws, track remaining points, handle busts and undo mistakes.

Games & Play: Games & Puzzles

32 apps

2048

Slide, combine, and make room. Bring matching tiles together to reach 2048.

Binary Grid

Fill each row and column with equal numbers of both colours. Never place three identical colours consecutively, and keep every completed row and column unique.

Box Pusher

A small room. A few boxes. Push each one onto a target without getting stuck.

Bridges

Join islands with horizontal or vertical bridges. Each island needs the number of bridges written on it, and every island must belong to one connected network.

Checkers

Move diagonally across the dark squares. Capture by jumping over an opposing piece. Captures are compulsory; reaching the far row crowns a king.

Codebreaker

Guess the four-colour code. A solid feedback dot means the right colour in the right place; a ring means the right colour in another place.

Dots and Boxes

Take turns drawing lines between dots. Completing a box claims it and gives you another move. The player with the most boxes wins.

Fillomino

Fill the grid so each connected group of equal numbers contains exactly that many cells. Clues stay fixed; equal-number regions must stay separate.

Five or More

Move a ball through empty squares to form a line of five or more matching colours. Moves that clear nothing add three balls from the preview.

Four in a Row

Pick a column. Plan your next move. Connect four discs before your opponent does.

Hitori

Shade squares so no unshaded number repeats in any row or column. Shaded squares cannot share an edge, and all unshaded squares must stay connected.

Inertia

Collect all the gems by sliding the ball. Walls, edges and stop circles halt a slide; touching a mine is fatal, but you can undo it.

Keen

Place 1 to N exactly once in every row and column. Each outlined cage must produce its target using the shown arithmetic operation.

Light Up

A lamp lights its row and column until a black square blocks it. Light all white squares without any lamp shining on another. Numbers count lamps immediately beside a black square.

Lights Out

One tap changes five lights. Find the pattern that switches the whole board off.

Mahjong Solitaire

Remove matching pairs of free tiles. A tile is free when nothing covers it and either its left or right side is open. Any flower matches a flower, and any season matches a season.

Mancala

Choose a pit on your bottom row and distribute its seeds around the board. Ending in your right-hand store gives another turn. Ending in an empty pit on your side captures the seeds opposite.

Minesweeper

A little logic, one square at a time. Clear the board without touching a mine.

Net

Rotate every tile until all pipes connect to the square source with no loose ends. Lit pipes are connected to the source.

Nonogram

Follow the numbers to uncover a hidden picture, one filled square at a time.

Numberlink

Join each pair of matching dots with a continuous path. Paths cannot cross and must cover the entire grid together.

Reversi

Turn the board in your favour. Capture your opponent’s discs and claim the corners.

Robots

Robots move toward you after each turn. Lure them into one another or into junk piles without getting caught.

Same Game

Remove connected groups of two or more matching tiles. Tiles fall down and empty columns close up. Larger groups score more, and clearing the board earns a bonus.

Shisen-Sho

Remove matching tiles that can be connected through empty space using no more than two turns. Paths may travel around the outside of the board.

Sightlines

Numbers count the dots visible in the four straight directions, excluding their own square. Walls block the view, and every dot must see at least one other dot.

Snake

Take a quick break. Gather the dots, grow your snake, and keep clear of your tail.

Tents

Place one tent beside each tree horizontally or vertically. Tents cannot touch, even diagonally. The outside numbers give tent counts for each row and column.

Tetravex

Move all tiles from the right tray to the left board. Numbers on every touching pair of edges must match.

Towers

Fill each row and column with heights 1 to N exactly once. An outside clue tells you how many towers are visible from that direction; taller towers hide shorter ones behind them.

Triples

Each move slides the tiles one step. A 1 and a 2 make 3; equal tiles of 3 or more combine with each other. The preview shows the next tile.

Yacht

Roll up to three times per turn, holding any dice you want to keep. Choose an unused scorecard category to finish the turn. Each category can be used once.

Games & Play: Puzzles & Games

1 app

Custom Crossword Maker

Make a crossword from your own words and clues. Preview the numbered grid, check which words fit, and download a printable puzzle with an answer key.

Games & Play: Tournaments & Fixtures

4 apps