Developer tool
Your files never leave your device
Check your Network tab and see
Work starts the moment you drop a file
No daily limit, no sign-up, no watermark
Anyone can Base64-decode a JWT payload and read the claims. Trust requires verifying the signature with the issuer's key — which should never be pasted into a web page. This tool is for debugging your own tokens in a tab you control, not for accepting tokens from strangers.
Standard three-part layout: header, payload, signature. URL-safe Base64 is normalised with padding before parse. Payload strings are decoded as UTF-8 so Unicode names and messages render correctly.
No HS256/RS256 verification, no JWKS fetch, no signing or minting tokens. If a token is expired, you will see exp in the note block — that is informational only until you verify with the issuer.
That is the promise behind every tool here. Files are read in your browser tab, processed there, and discarded when you close it — never uploaded to our servers.
Encode to Base64 or decode from Base64 instantly in your browser.
Format, validate, prettify and beautify your JSON data instantly.
Convert Unix epoch timestamps to human-readable dates, and vice versa.
MD5 for checksums plus SHA-1, SHA-256, and SHA-512 via Web Crypto — all in your browser, nothing uploaded.
Test, visualize, and debug Regular Expressions instantly in your browser.
Generate strong, secure, and random passwords locally in your browser.
