Developer Guide5 min read Updated August 24, 2026
Decoding & Inspecting JSON Web Tokens (JWT)
Pasting production OAuth JWT tokens into public websites is a major security risk. Learn how to decode JWT headers and payload claims 100% locally.
Quick Takeaway
Use our JWT Decoder to paste access tokens, inspect payload claims, view human-readable expiration dates (exp), and verify token scopes privately.
Understanding JWT Structure (Header.Payload.Signature)
JWTs consist of 3 Base64URL-encoded strings separated by dots: Header (algorithm & token type), Payload (user claims & exp), and Signature.
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Frequently Asked Questions
Is my JWT token sent to any external server?↓
No. The JWT parsing algorithm runs completely in local browser RAM.