Developer Tools
7 free developer tools, all running privately in your browser.
These free developer tools cover the everyday tasks that interrupt coding: formatting JSON, testing regular expressions, decoding JWTs, escaping HTML, converting CSV to JSON, and more. Everything runs client-side, so you can safely paste tokens and data without it touching a server.
Developer utilities live or die on privacy and speed. Pasting a JWT or a chunk of production data into a random website is a real risk; these tools do all parsing locally in your browser, so nothing is transmitted. For deeper background, our blog explains how JWTs, hashing, and Base64 actually work.
JSON Formatter
Format, validate, and minify JSON data.
Regex Tester
Test regular expressions against sample text.
Markdown Previewer
Write Markdown and preview the rendered output.
CSS Gradient Generator
Design CSS gradients and copy the code.
JWT Decoder
Decode JWT header and payload instantly.
CSV to JSON Converter
Convert CSV data to JSON and back.
HTML Escape / Unescape
Escape or unescape HTML entities.
Frequently asked questions
Is it safe to paste tokens and data here?
Yes. All processing happens locally in your browser - decoding a JWT or formatting JSON never sends your data anywhere. That said, never paste production secrets into any tool you haven't verified runs client-side.