JWT Decoder

How JWT Decoding Works

A JWT consists of three Base64URL-encoded parts separated by dots: Header.Payload.Signature

JWT Structure

• Header: Contains the algorithm (e.g., HS256, RS256) and token type (JWT).
• Payload: Contains claims — statements about the user and metadata. Common claims include sub (subject), iat (issued at), exp (expiration), and custom data.
• Signature: Created by signing the encoded header and payload with a secret key. Used for verification.

Common Claims

• sub — Subject (user identifier)
• iat — Issued At (Unix timestamp)
• exp — Expiration Time (Unix timestamp)
• nbf — Not Before (Unix timestamp)
• iss — Issuer
• aud — Audience