Free Developer Tools Online
A curated collection of fast, browser-based utilities for everyday developer tasks. No data collection. No server calls. Just tools that work.
All Developer Tools
All 15 tools run in your browser — no data leaves your machine.
JSON Formatter & Validator
Format, validate, and minify JSON instantly. Upload files, detect errors with line numbers, and download results.
JWT Decoder
Decode JWT tokens instantly. View header, payload, expiry status, and token details — entirely client-side.
UUID Generator
Generate UUID v4 values instantly. Create single or bulk UUIDs, copy to clipboard, or download as a text file.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to plain text instantly. Supports standard and URL-safe Base64.
URL Encoder / Decoder
Encode special characters in URLs or decode percent-encoded strings instantly. Works with full URLs and individual components.
Timestamp Converter
Convert Unix timestamps to readable dates, or convert dates back to Unix timestamps. Supports seconds, milliseconds, and multiple date formats.
JSON to YAML Converter
Convert JSON data to YAML format instantly. Clean, readable YAML output with proper indentation. No libraries, runs entirely in your browser.
JSON to TypeScript
Automatically generate TypeScript interfaces from JSON data. Handles nested objects, arrays, and infers types correctly.
Regex Tester
Test regular expressions against text in real time. See matches highlighted, get match count, and capture groups. Supports all JS regex flags.
Text Diff Checker
Compare two texts and see the differences highlighted. Line-by-line diff view shows additions, deletions, and unchanged lines clearly.
SQL Formatter
Format and beautify SQL queries with proper indentation and keyword casing. Makes minified or messy SQL readable instantly.
Hash Generator
Generate cryptographic hashes (MD5, SHA-1, SHA-256, SHA-384, SHA-512) from text or files. Runs entirely in your browser.
Color Converter
Convert colors between HEX, RGB, HSL, and HSV formats instantly. Includes a live color preview and picker.
Markdown Preview
Write Markdown and preview the rendered HTML output in real time. Supports headings, lists, code blocks, links, and more.
Image Converter
Convert images between PNG, JPG, WebP and AVIF instantly. Batch convert several files, set quality, and downscale — all in your browser.
Why Dev Tools Hub?
Privacy First
Every tool runs 100% in your browser. Your data is never sent to any server.
Instant Results
No loading spinners, no API calls. Tools respond the moment you click.
Always Free
Core utilities will always be free. No paywalls, no credit card required.
Works Everywhere
Fully responsive. Use on desktop, tablet, or mobile — all modern browsers supported.