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Developer Tools

273 apps

Developer Tools: Errors & Network

Developer Tools: Accessibility & Quality

Developer Tools: Content & Structure

Developer Tools: Format & Encode

Developer Tools: Format & Validate

Developer Tools: Convert & Clean

Developer Tools: Explore & Extract

Developer Tools: IDs & Tokens

Developer Tools: Time & Automation

Developer Tools: Test & Compare

Developer Tools: Diff & Patch

Developer Tools: Mock Data

Custom Fake Dataset Generator

Name your columns, pick simple fake field types, and create a repeatable JSON or CSV dataset.

Fake Address Generator

Create localized street addresses, cities, regions, postal codes, countries, and optional map coordinates.

Fake Appointment Dataset Generator

Create safe sample appointments with clients, services, staff, times, lengths, prices, and status.

Fake Book Metadata Generator

Create sample book titles, authors, genres, publishers, formats, series, ISBNs, and optional summaries.

Fake Company Generator

Create made-up company names, taglines, industries, websites, emails, and phone numbers.

Fake Contact List Generator

Build a sample contact list with names, emails, phone numbers, companies, and optional addresses.

Fake Food Menu Generator

Create sample dishes with descriptions, food styles, ingredients, spice notes, prices, and availability.

Fake Order Generator

Create nested test orders with customers, line items, quantities, totals, dates, and order status.

Fake Person Generator

Create realistic names, birthdays, jobs, and short bios for tests, demos, and practice projects.

Fake Product Catalog Generator

Create sample products with SKUs, names, departments, descriptions, materials, colours, and prices.

Fake Vehicle Dataset Generator

Create sample vehicles with makers, models, types, fuel, colours, and optional VIN and plate values.

Internet Test Data Generator

Create sample usernames, emails, domains, URLs, IP addresses, user agents, and optional passwords.

Localized Fake Data Sampler

Compare names, addresses, phone numbers, companies, and products from two language or country settings.

Mock API Response Generator

Create a realistic users, products, or orders API response with optional page details.

SQL Seed Data Generator

Create safe INSERT statements for sample users, products, or companies in PostgreSQL, MySQL, or SQLite.

Test Payment Data Generator

Create clearly fake card and bank fields for form tests. These values are not for real payments.

Developer Tools: Architecture & Documentation

Developer Tools: Build Templates

Developer Tools: Code & Configuration

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