encoding_decoding_jwt
Offline JWT decoder and claim inspector: splits token, decodes header and payload, annotates claims with timestamps and expiration check.
Instructions
JWT Decoder and Claim Inspector. Decode and inspect a JSON Web Token offline: split it into header, payload, and signature, Base64URL-decode the header and payload JSON, and annotate every payload claim (with human-readable timestamps and an EXPIRED flag for past exp). This tool only decodes and does not fetch JWKS or verify the signature cryptographically; use security_jwt_generator_validator when you need to verify an HMAC or asymmetric signature, check exp/nbf against a secret or key, or assemble and sign a new token. Runs locally on the token you provide: read-only, non-destructive, contacts no external service, and is rate-limited (60 requests/minute for anonymous callers). Returns the decoded header and payload, the three raw token parts, a structure-status object, and a per-claim analysis map.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| token | Yes | The JSON Web Token to decode, as a compact dot-separated string of three Base64URL parts (header then payload then signature). Must not be blank. Whitespace is trimmed before parsing. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| success | No | True when the token had a valid three-part structure and both header and payload decoded; otherwise the endpoint returns HTTP 400. | |
| input | No | The submitted token string, echoed back. | |
| decodedJWT | No | The decoded token sections. header and payload are null when decoding failed. | |
| tokenParts | No | The token split on dots, before decoding. Normally three elements (header, payload, signature). | |
| tokenStatus | No | Structural assessment of the token. | |
| claimsAnalysis | No | Per-claim breakdown keyed by claim name; each entry describes one payload claim. Empty when decoding failed. | |
| error | No | A high-level parse error message when decoding failed, or null on success. |