Encoding & Cryptography Tools
Hashes, Base64, JWTs, HMACs and encryption — computed in your browser.
- Base64 Encoder & DecoderBoth directions, Unicode-safe, with the URL-safe alphabet when you need it.Runs in your browser
- JWT DecoderRead a token’s header and claims, and see what it says about itself. Decoding, not verification.Runs in your browser
- URL Encoder & DecoderPercent-encoding in all three flavours, side by side, so you can see which one you want.Runs in your browser
What these tools have in common
These are the tools you reach for when something is not the shape you expected: a token you need to read, a checksum that has to match, a payload that arrived Base64-encoded, a signature you want to reproduce.
Every one of them runs on the Web Crypto API or an equivalent browser primitive, which matters more here than anywhere else on the site. Pasting a signing key or a production JWT into a page that posts it to a server is a genuine incident, and plenty of popular tools do exactly that. Nothing in this section sends your input anywhere.
Where an algorithm is obsolete for its original purpose — MD5 and SHA-1 for passwords, most obviously — the page says so plainly and explains what it is still legitimately used for, rather than refusing to compute it.