Free Online Developer Tools & Utilities

A collection of free, fast, and reliable online developer tools for your daily tasks — format JSON, encode Base64, generate UUIDs and secure passwords, convert timestamps, and more. Everything runs client-side in your browser, so your data stays private and secure.

🔌Now available as MCP for VS Code, Claude & AI Assistants

Browse Developer Tools

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JSON Formatter

Format, validate, and prettify JSON data with syntax highlighting and error detection.

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JSON to TOON Converter

Convert JSON to TOON (Token-Oriented Object Notation) and back. Optimize tokens for Large Language Model prompts.

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Password Generator

Generate secure passwords with custom settings.

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UUID Generator

Generate Version 1, 4, and 7 UUIDs for applications and databases.

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CRON Expression Generator

Build and validate CRON expressions with human-readable descriptions and examples.

Timestamp Converter

Convert Unix timestamps to human-readable dates with timezone support and batch processing.

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Lorem Ipsum Generator

Generate placeholder text for layouts and designs with custom length options.

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Color Converter

Convert colors between HEX, RGB, HSL, HSV, CMYK, and OKLCH formats with decimal precision and live preview.

Favicon Generator

Generate favicon files from any image. Create ICO, PNG, and webmanifest for all devices and browsers.

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SVG to EPS Converter

BETA

Convert SVG vector graphics to EPS (Encapsulated PostScript). Paths, shapes, transforms, and colors — fully client-side.

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Base64 Encoder/Decoder

Encode and decode Base64 strings quickly and easily with real-time conversion.

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URL Encoder/Decoder

Encode and decode URLs for safe transmission with multiple encoding modes and batch processing.

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Text Diff / Comparison Tool

Compare text files side-by-side with highlighted differences and merge capabilities.

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Markdown Table Formatter

Tidy up markdown tables with aligned columns and clean separator rows for readable documentation.

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JWT Debugger

Decode, verify, and encode JWT tokens with support for all major signing algorithms.

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Hash Generator

Generate secure hash values using multiple algorithms including SHA-256, MD5, bcrypt, and more with performance monitoring.

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QR Code Generator

Generate QR codes from text, URLs, and data with customizable size and format.

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Color Palette Generator

Generate beautiful color palettes with hex, and RGB values.

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RegEx Tester

Test and debug regular expressions with live matching.

Why Use DevTools?

DevTools is a free collection of online developer utilities built for speed and privacy. Whether you need to format and validate JSON, encode or decode Base64 and URLs, generate UUIDs, create strong passwords, or convert Unix timestamps, every tool works instantly — no sign-up, no installs, and no limits.

Every tool runs entirely client-side in your browser. Your data is never uploaded to a server, logged, or stored, which makes DevTools safe for sensitive inputs like JWT tokens, passwords, and private JSON payloads. Because there are no server round-trips, results are generated in real time, even for large, multi-megabyte inputs.

From formatters and encoders to generators, converters, and analyzers, DevTools brings the everyday utilities developers reach for into one fast, reliable place — and the same tools are available as an MCP server for Claude, VS Code, and other AI assistants.

Explore Tools by Category

Formatters & Analyzers

Format, validate, and inspect your data. Beautify and validate JSON, align Markdown tables, decode and verify JWT tokens, generate SHA-256, MD5, and bcrypt hashes, and compare text or code with a line-by-line diff.

Encoders & Decoders

Encode and decode data safely. Convert text to and from Base64, escape and unescape URLs, and switch between standard and URL-safe formats — all processed locally in your browser.

Generators

Generate the values you need on demand: cryptographically secure passwords with strength scoring, UUID v1, v4, and v7, CRON expressions, Lorem Ipsum placeholder text, and favicons from any image.

Converters

Convert between formats instantly. Turn Unix timestamps into human-readable dates across timezones, convert colors between HEX, RGB, HSL, and OKLCH, and convert JSON to TOON to save tokens on LLM prompts.

Frequently Asked Questions

Are these developer tools free to use?

Yes, every tool on DevTools is completely free with no sign-up, no account, and no usage limits. You can format JSON, encode Base64, generate UUIDs and passwords, convert timestamps, and more as often as you need.

Is my data safe? Where is it processed?

All tools run 100% client-side in your browser. Your JSON, passwords, tokens, and other inputs never leave your device or get uploaded to a server, so your data stays private and secure.

What developer tools are available?

DevTools includes a JSON formatter and validator, Base64 encoder/decoder, URL encoder/decoder, password generator, UUID generator (v1, v4, v7), CRON expression generator, timestamp converter, Lorem Ipsum generator, color converter, text diff tool, Markdown table formatter, JWT debugger, hash generator, and a favicon generator.

Do I need to install anything or create an account?

No installation and no account are required. Every tool works instantly in your browser. The same tools are also available as an MCP server for Claude, VS Code, and other AI assistants if you prefer to use them in your AI workflows.

Can these tools handle large inputs?

Yes. The tools process data in your browser and are optimized to handle large inputs efficiently, from multi-megabyte JSON files to bulk UUID or password generation, with real-time results.

Are my results stored or logged anywhere?

No. Because processing happens entirely on the client side, nothing you enter or generate is stored, logged, or transmitted. Closing or refreshing the page clears everything.