Inspect token claims
Read issuer, subject, audience and time-related claims while debugging authentication flows.
100% local · files never leave your browser
Inspect tool
JWT Decoder
Decode JWT headers and payloads locally in your browser. No token upload, account or signature-verification claim.
✓ Free to use✓ No signup✓ Runs locally
125 bytes · local only
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Processed entirely in this tab
Your input and result are not sent to JSON Hearth or stored on a server.
When to use it
What JWT Decoder helps you do
JWT decoding makes the Base64URL-encoded header and payload readable. It does not establish that a token is authentic or safe to trust.
Review token structure
Check the declared algorithm and payload shape without sending the token to a remote decoder.
Diagnose expiry issues
Inspect issued-at and expiration values as part of troubleshooting, while still verifying them in trusted code.
Important limitations
What to check before using the result
- Decoding does not verify the signature, issuer, audience, expiry or any authorization decision.
- Treat bearer tokens as secrets and avoid sharing decoded or raw values unnecessarily.
Common questions
About JWT Decoder
Does decoding a JWT verify its signature?
No. Anyone can decode the header and payload. Verification requires the correct key and trusted validation logic.
Can I trust claims shown by a decoder?
Only after a trusted system has verified the signature and enforced issuer, audience, expiry and application rules.