How to decode a JWT online for free

Decoding a JWT means Base64URL-decoding the header and payload so you can read algorithm, claims, and expiry. You can do it in code, a CLI, or a free online JWT decoder that runs in your browser.

Decode a JWT with Jigglify (30 seconds)

1. Open the JWT decoder.
2. Paste the full three-part token (including dots), or click Sample.
3. Click the arrow to decode header and payload.
4. Check algorithm and expiry hints, then explore or copy the payload JSON.

What to look for

• alg - signing algorithm hint (still verify on the server with allowed algorithms only).
• exp / iat - expiry and issued-at; common causes of unexpected 401s.
• Custom claims - roles, scopes, tenant ids - confirm they match what your app expects.

Why decode locally?

Tokens often contain emails, internal ids, or scopes. A browser-only decoder keeps that data on your device while you debug auth flows, refresh logic, or middleware failures.

Common decode failures

Missing segments, truncated Base64URL, or non-JSON parts will fail. Paste the complete header.payload.signature string with no line breaks in the middle of a segment.

Decode JWTs free - inspect claims locally with no account and no upload.
Open the free JWT decoder →

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