JWT Decoder
Decode JSON Web Tokens locally. Inspect headers and payload claims without sending sensitive tokens to a server.
Decoded Data
Error:
Header
Payload (Claims)
Paste a valid JWT to see decoded contents.
Frequently Asked Questions
Is my token sent to your servers?
No. Decoding happens entirely in your browser using JavaScript's native atob decoding functions. Your tokens never leave your machine.
Does this tool verify the signature?
No, this tool only decodes the Base64Url encoded header and payload to make them readable. To verify a signature, you need the secret key used to sign the token.