JWT Decoder
Paste a JSON Web Token to inspect its header and payload claims — decoded locally, so the token never leaves your browser.
JWT Decoder / Encoder
Token never leaves your browser — all crypto is local
Signature Verification
Generated token
About this tool
A JSON Web Token (JWT) packs a header, a payload of claims and a signature into one compact string. This decoder splits the token apart and shows the header and payload as formatted JSON, highlighting time-based claims such as iat, nbf and exp so you can tell at a glance whether a token has expired.
Decoding happens entirely in your browser — the token is never transmitted or logged. That matters: a JWT often grants access to a real account, so it should never be pasted into a tool that ships it off to a server.