Free Online Developer Tools
The small utilities you reach for a dozen times a day, without the ads, sign-ups and sketchy data handling. Format a JSON payload, decode a Base64 string, escape a URL, or hash a value – instantly, and without sending your data to anyone.
Choose a tool
JSON Formatter & Validator
Free JSON formatter and validator: beautify with 2 or 4 spaces or tabs, minify, and get exact line and column numbers for syntax errors.
Base64 Encoder & Decoder
Free Base64 encoder and decoder with full Unicode support.
URL Encoder & Decoder
Free URL encoder and decoder.
SHA Hash Generator
Free hash generator: create SHA-1, SHA-256, SHA-384 and SHA-512 hashes from any text instantly in your browser using the Web Crypto API.
Safe for real payloads
Developers routinely paste API responses, tokens and config into online formatters without thinking about where that data goes. These tools run entirely in your browser: no request is made, nothing is logged, and you can use them on production data without filing a security exception.
Helpful error messages
Our JSON formatter does not just say “invalid”. It tells you the line and column of the failure and what the parser expected, so you can find the trailing comma or unescaped quote in seconds. Encoders explain the difference between encodeURI and encodeURIComponent rather than leaving you to guess.
Frequently asked questions
Is my data sent to a server?
No. Every developer tool here runs locally in your browser using standard Web APIs, so pasted payloads, tokens and config never leave your machine.
Why is there no MD5 hash option?
MD5 and SHA-1 are broken for security purposes. We include SHA-1 only because legacy systems still require it, and recommend SHA-256 or stronger for anything that matters.
What is the difference between encodeURI and encodeURIComponent?
encodeURI keeps the characters that give a URL its structure (: / ? & =) and is for encoding a whole URL. encodeURIComponent escapes those too, and is for a single query value or path segment.
Is there a size limit on the JSON formatter?
No hard limit, but very large documents (tens of megabytes) may be slow because parsing happens on your device.
Do these tools work offline?
Yes, once the page has loaded.