// free-toolJWT → JSON
Paste a JSON Web Token and see its header and payload decoded into formatted JSON, with the timestamp claims (iat, exp, nbf) translated into readable dates and a clear expired / valid indicator. Decoding is pure Base64 — the token never leaves your browser, and the signature is not (and cannot be) verified without the secret.
no signup · no watermark · unlimited use
The token is decoded locally and never transmitted — nothing leaves your browser. Still, treat production tokens as secrets: prefer expired or development tokens when possible.
No — signature verification requires the signing secret or public key. This tool decodes the (Base64-encoded, unencrypted) header and payload, which is what you need for debugging claims.
Encode any text to Base64 — Unicode-safe.
Decode Base64 back to readable text instantly.
Percent-encode text for safe use in URLs and query strings.
Decode percent-encoded URLs back to readable text.
Convert text to its hexadecimal byte representation.
Decode hexadecimal bytes back into readable text.
I build fast, privacy-first web applications with Next.js — these converters run entirely in the browser, and yours can too.