Developer Tools
Everyday utilities for JSON, JWT, Base64, URLs, hashing and regular expressions. Each one runs in your browser: nothing you paste is sent to a server.
- JSON Formatter and ValidatorCatches duplicate keys and precision loss on large integers.
- JWT DecoderDecodes only, never verifies. The token is not sent anywhere.
- Base64 Encoder and DecoderCorrect UTF-8 handling, plus the URL-safe alphabet.
- URL Encoder and DecoderExplicit choice between encodeURI and encodeURIComponent.
- SHA Hash GeneratorSHA-1, SHA-256, SHA-384 and SHA-512 via Web Crypto.
- Regex TesterMatching runs in a time-boxed Worker, so the tab cannot lock.
Fully client-side
None of these tools transmit what you type. Once the page has loaded you can disconnect entirely and they keep working.