JWT decoder — private, in-browser
Paste a JWT at the TokenPeek console prompt to split header, payload, and signature. Header and payload are Base64URL-decoded and pretty-printed as JSON when possible. The signature is displayed raw and is not verified.
TokenPeek never asks for a signing secret and does not forge or crack tokens. Use the sample button to try a demo token, then verify in DevTools Network that nothing posts your JWT.