Free Developer Tools Online
A complete suite of free, browser-based developer tools for software engineers, full-stack developers, and DevOps professionals. Format and validate JSON, compare code with diff checker, test regular expressions in real time, decode JWT tokens, encode Base64, beautify SQL queries, and more — all running locally in your browser with zero data sent to any server.
Tools Every Developer Needs Daily
Modern software development involves constant context-switching between tools — formatting an API response, validating a regex, comparing two config files, decoding a JWT. Opening separate websites for each task slows you down. YourToolsKit puts 18 essential developer tools in one place, all browser-based, all instant, all free.
All Free Developer Tools Online
18 tools · Free · Browser-based · No sign-up
Format, beautify, validate, and minify JSON online free. Instantly spot syntax errors with clear highlighting.
Convert JSON arrays to CSV with table preview and download. Handles nested objects and custom delimiters.
Convert JSON to well-formed XML instantly. Handles arrays, nested objects, and custom root elements.
Parse XML and convert to clean JSON output. Handles attributes, namespaces, and nested elements.
Test and debug regular expressions in real time. Highlights all matches, shows capture groups, supports all flags.
Decode and inspect JWT tokens instantly. View header, payload, expiry, and signature. Check token validity.
Beautify or minify HTML code. Auto-indents nested tags, normalizes attributes. Side-by-side preview.
Minify CSS to reduce file size or beautify CSS for readability. Shows exact byte savings.
Minify JavaScript to reduce bundle size or beautify minified JS for readability.
Build cron expressions visually. Get human-readable descriptions and next 5 run times.
Compare text, JS, CSS, TSX, JSON side by side. Highlights every addition and deletion instantly.
Encode text to Base64 or decode Base64 strings. Supports standard and URL-safe Base64.
Convert images to Base64 data URIs for HTML, CSS, and JavaScript. Supports JPEG, PNG, WebP, SVG.
Percent-encode URLs or decode encoded strings. Handles all special characters.
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly. All hashing done locally.
Convert Markdown to HTML with live preview. Supports tables, code blocks, GitHub Flavored Markdown.
Format, beautify, and minify SQL queries. Supports MySQL, PostgreSQL, SQLite, SQL Server.
Build UTM tracking URLs for Google Analytics campaigns. Copy and share instantly.
Common Workflows
Step-by-step guides for the most common use cases
- Open JSON Formatter
- Paste the raw API response
- Beautify to see structure clearly
- Validate to catch syntax errors
- Use JSON → CSV to export data
- Open JWT Decoder
- Paste your JWT token
- See header, payload, and expiry
- Check if token is expired
- Use Hash Generator to verify signatures
- Open Diff Checker
- Paste original code on the left
- Paste modified code on the right
- See every change highlighted
- Works with JS, TS, CSS, JSON, HTML
- Open Cron Generator
- Set your schedule visually
- Get the cron expression
- See human-readable description
- View next 5 run times
Frequently Asked Questions
Everything you need to know about these tools
Yes — all 18 developer tools are completely free with no sign-up, no account, and no usage limits. Every tool runs entirely in your browser using JavaScript. No data is ever sent to any server. You can use them as many times as you want.
No installation required. All tools run directly in your web browser. Open the page, paste your input, and get the result instantly. Works on Chrome, Firefox, Safari, and Edge on any device including mobile.
Yes — all processing happens locally in your browser. Your JSON, code, tokens, and data never leave your device. There are no server-side components, no logging, and no analytics on your input data. Even the JWT decoder works entirely client-side.
Open our JSON Formatter, paste your JSON into the input box, and click Beautify. The formatter adds proper indentation and highlights syntax errors instantly. You can also minify JSON back to a single line for production use, or validate JSON without formatting.
Yes — the Diff Checker supports plain text, JavaScript, TypeScript, TSX, CSS, JSON, HTML, and any other text format. Paste your two versions, click Compare, and see every addition highlighted in green and every deletion in red.
Base64 is used to encode binary data as text for safe transmission in JSON APIs, embed images in CSS as data URIs, store binary blobs in HTML, and encode credentials in HTTP Basic authentication headers. Our Base64 encoder supports both standard Base64 and URL-safe Base64url encoding.
Related Tool Categories
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