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New additions for files, fonts, code, audio, and data. Explore 394 new tools

Browse calculators by topic Finance, everyday life, construction, conversions, and more.

273 apps · Showing 97–192

Developer Tools: Build Templates

Liquid Template Playground

Render a safe, bounded Liquid template and see the output as plain text.

Order Confirmation Liquid Template Tester

Build a clear order confirmation from customer, order, and shop fields.

Shopify Product Card Template Tester

Test product fields, price math, tags, and availability in a Liquid card template.

Developer Tools: Code & Configuration

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

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: Common Formats

Coupon Code Regex Sample Generator

Generate sample coupon codes from a simple editable promotion pattern.

Date Regex Sample Generator

Generate ISO-shaped date strings for parser and form tests, then check real calendar rules separately.

Email Regex Sample Generator

Generate example email addresses on reserved example and test domains.

Filename Regex Sample Generator

Generate lowercase file names with common test extensions and no folder paths.

Hex Color Regex Sample Generator

Generate uppercase six-digit hexadecimal colors for design and form tests.

IPv4 Regex Sample Generator

Generate IPv4 values whose four number parts stay between 0 and 255.

Order Number Regex Sample Generator

Generate order-number examples for receipt, search, and import testing.

Phone Regex Sample Generator

Generate North American phone-shaped examples for formatting and input tests.

SKU Regex Sample Generator

Generate product SKU examples with letters, digits, and fixed separators.

Tracking Code Regex Sample Generator

Generate fake tracking-shaped codes without using a real carrier number.

URL Slug Regex Sample Generator

Generate lowercase, hyphen-separated slug values for route and form testing.

Username Regex Sample Generator

Generate lowercase usernames that follow a clear length and character rule.

Developer Tools: CSS & JavaScript

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

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

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: Explore a Pattern

Long Regex Sample Finder

Generate many matches and keep the longest examples found in that sample run.

Regex Coverage Pack Maker

Make a small test pack that covers several lengths and removes duplicate strings.

Regex Sample Length Explorer

Generate a test batch and compare its shortest, longest, and average string lengths.

Short Regex Sample Finder

Generate many matches and keep the shortest examples found in that sample run.

Developer Tools: Filter & Reshape

JSON Array Filter

Filter a JSON array with a clear JSONata condition and keep the matching objects.

JSON Array Flattener

Pull values from arrays inside records into one simple result sequence.

JSON Array Grouper

Group array records by a field and return one object with a key for each group.

JSON Array Sorter

Sort an array by text or numbers with JSONata's order-by operator.

JSON Field Picker

Turn each object into a smaller object with a chosen set of fields.

JSON Field Renamer

Build new objects with renamed fields while keeping the original JSON unchanged.

JSON Object Reshaper

Combine fields, filters, and nested results into a cleaner object for another system.

Developer Tools: Find Code Parts

JavaScript Arrow Function Finder

List arrow functions with inferred names, parameters, async state, and source lines.

JavaScript Async Function Finder

Find async declarations, expressions, and arrows with names, parameters, and lines.

JavaScript Await Expression Finder

List awaited expressions with their readable source text and exact line.

JavaScript Call Expression Finder

List function and method calls with readable callee names, argument counts, and lines.

JavaScript Class Inventory

List class declarations and expressions with inheritance and method counts.

JavaScript Comment Extractor

Extract comments with their type, text, line, and character count.

JavaScript Dynamic Import Finder

List dynamic import expressions, source values, and exact locations.

JavaScript Event Listener Finder

List event listener calls, target expressions, event names, and lines.

JavaScript Export Inventory

Find export statements, names, source modules, lines, and export kinds.

JavaScript Function Inventory

Find function declarations and expressions with names, parameters, lines, and flags.

JavaScript Import Inventory

Find static imports, source packages, local names, and import kinds.

JavaScript Number Literal Extractor

Extract decimal, hex, binary, octal, bigint, and exponent number literals.

JavaScript Object Key Finder

Find object property keys, method keys, computed state, and source lines.

JavaScript Optional Chaining Finder

List optional member and call expressions with their source lines.

JavaScript String Literal Extractor

Extract string and template text with quote type, length, and source line.

JavaScript Variable Declaration Finder

Find declared names, declaration kinds, initial values, lines, and nesting depth.

Developer Tools: Generate Samples

Bulk Regex Sample Generator

Generate up to 250 matching strings for forms, imports, and test fixtures.

Regex Example Generator

Enter a regular expression and make clear example strings that match it.

Seeded Regex Sample Generator

Use a seed so the same pattern and settings make the same strings again.

Unique Regex Sample Generator

Try extra generations and keep only distinct strings that match your pattern.