17 tools · all run in your browser
Developer tools
Everyday utilities for developers: format and validate JSON, pretty-print XML and CSS, encode and decode Base64, URLs and HTML entities, generate UUIDs and cryptographic hashes, convert timestamps and colours, decode JWTs and test regular expressions.
JSON3
Generators1
Design1
Encoding5
- Base64 EncoderEncode text or files to Base64, Base64URL or data URLs.
- Base64 DecoderDecode Base64 to text, or download the decoded file.
- URL EncoderPercent-encode text for use in URLs and query strings.
- URL DecoderDecode %-encoded URLs and inspect their parameters.
- HTML Entity Encoder / DecoderEscape special characters as HTML entities, or decode them.
Text1
Security3
Time1
Formatters2
Developer data is often sensitive — API responses, tokens, configuration. All of these tools run client-side using standard browser APIs such as Web Crypto, so you can paste production data without it leaving your machine.
Where a standard exists, tools follow it exactly: RFC 4648 for Base64, RFC 3986 for URL encoding, RFC 9562 for UUIDs and FIPS 180-4 for SHA hashes.
Frequently asked questions
Is it safe to paste API tokens or JWTs here?
The tools run in your browser and nothing is transmitted. As a general security practice, rotate any secret that you have exposed in places you do not control.
Which hash algorithms are supported?
MD5, SHA-1, SHA-256, SHA-384 and SHA-512. SHA hashes use your browser's Web Crypto implementation.