JWT Decoder & Security Inspector

Inspect the visible structure and claims of a compact token.

Processed in your browser. Your input is not uploaded.

Paste a compact token

Add one three-part JWS or five-part JWE serialization. It stays in page memory.

0 / 32,768 bytes

Visible structure, claims and boundaries will appear here after inspection.

This page decodes compact-token evidence locally. It does not upload, validate or modify the token.

1
Paste one compact token
Add a three-part JWS or five-part JWE serialization. It stays in page memory and is not uploaded.
2
Inspect visible evidence
Review its declared header, readable claims, segment sizes and local clock observations without validating a signature.
3
Use only the lead you choose
Copy local evidence, or investigate an eligible claimed issuer. The token and other token values never enter Coeus.

This tool does not check a signature, decrypt JWE contents, fetch keys, follow header URLs or evaluate a relying party's policy.

Issuer, audience, subject and time values describe what the token says. A device-clock comparison cannot establish validity, acceptance or safety.

Token text, signatures, subjects, key references and header URLs are never sent, saved or handed to Coeus.

Keep working with the same local-first toolkit.