Free Online Developer Tools
Speed up your daily development workflow with our collection of 17 browser-based utilities built for developers, DevOps engineers, and technical writers. Format and validate JSON or XML in one click, minify CSS for production builds, test regular expressions with real-time match highlighting, and generate secure hashes or UUIDs without installing anything. Need to decode a JWT during debugging, convert a Unix timestamp from a log file, or switch variable names between camelCase and snake_case? Every tool is right here. All processing runs entirely inside your browser — your code, tokens, and data never leave your device. No accounts, no rate limits, no watermarks. Just open a tool and start working. Whether you are building APIs, reviewing pull requests, or writing documentation, these free developer tools eliminate context-switching and save you time every single day.
JSON Formatter
Format, beautify, minify and validate JSON with syntax highlighting.
Try it freeCSS Minifier
Minify and compress CSS code to reduce file size instantly.
Try it freeText Case Converter
Convert text between camelCase, snake_case, UPPER, lower, and more.
Try it freePassword Generator
Generate strong, secure random passwords with custom rules.
Try it freeWord Counter
Count words, characters, sentences and paragraphs in any text.
Try it freeURL Encoder/Decoder
Encode or decode URLs and query string parameters.
Try it freeRegex Tester
Test and debug regular expressions with real-time matching and highlights.
Try it freeMarkdown Editor
Write and preview Markdown with live rendering side by side.
Try it freeTimestamp Converter
Convert between Unix timestamps and human-readable dates.
Try it freeHash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text.
Try it freeUUID Generator
Generate RFC-compliant UUIDs (v4) with one click.
Try it freeYAML Formatter
Format, validate and beautify YAML documents instantly.
Try it freeCSV to JSON
Convert CSV data to JSON format with automatic header detection.
Try it freeHTML Entity Encoder
Encode and decode HTML entities to prevent XSS and display issues.
Try it freeJWT Decoder
Decode and inspect JSON Web Tokens — header, payload and signature.
Try it freeBase Converter
Convert numbers between binary, octal, decimal and hexadecimal.
Try it freeXML Formatter
Format and beautify XML documents with proper indentation.
Try it freeFrequently Asked Questions
Are these developer tools really free?
Yes, every developer tool on FreeAIKit is 100% free with no usage limits, no signup required, and no watermarks. All tools run entirely in your browser so your data never leaves your device.
Do you upload my code or data to a server?
No. All processing happens locally in your browser using JavaScript. Your code, JSON, CSS, passwords, and any other input never leave your machine. There is no server-side processing involved.
Can I use these tools on mobile devices?
Yes. All developer tools are fully responsive and work on phones, tablets, and desktops. The interfaces adapt to smaller screens so you can format JSON, test regex, or generate passwords on the go.
What browsers are supported?
These tools work in all modern browsers including Chrome, Firefox, Safari, Edge, and Brave. They require JavaScript enabled and support HTML5 standards. No browser extensions or plugins are needed.