Developer Tools
Formatters, encoders and testers for developers and technical users.
6 free tools · 100% in your browser
JSON Formatter & Validator
Format, beautify, minify and validate JSON with clear error messages.
Open toolBase64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to plain text.
Open toolRegex Tester
Test regular expressions against sample text with live match highlighting.
Open toolMarkdown to HTML Converter
Convert Markdown into clean HTML with a live preview.
Open toolInvoice Generator
Create a professional invoice and download it as a PDF.
Open toolGrammar Checker
Check your writing for grammar, spelling and style mistakes.
Open toolAbout developer tools
A focused set of utilities for developers and technical users: format and validate JSON, encode or decode Base64, test regular expressions, convert Markdown to HTML and more. No noise, just the tool.
They run client-side, so your code and data stay on your machine, and they load fast. Bookmark the ones you use daily, since they keep working offline once the page has loaded.
Frequently asked questions
Is my code or pasted data sent anywhere?
No. These developer tools process everything in your browser; nothing you paste is uploaded or logged.
Are these tools free for commercial use?
Yes. They are free for personal and commercial work, with no account required.