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JWT Decoder

100% Client-Side Private — Zero Server Uploads

Decode and inspect JSON Web Tokens. View header, payload, and expiration status.

How do I use JWT Decoder?

1

Paste your JWT token into the input field.

2

Click 'Decode JWT' to parse the token.

3

View the decoded header, payload claims, and signature section.

4

Check expiration status and issue timestamps.

What features does JWT Decoder offer?

Pure client-side Base64URL decoding — no server, no network requests

Automatic exp and iat timestamp validation and human-readable display

Structured JSON output for header and payload

100% Private — your JWT token never leaves your browser

Frequently Asked Questions about JWT Decoder

Does this tool verify JWT signatures?

No. This tool decodes and inspects the JWT payload. Signature verification requires the signing key or secret, which should never be entered into a browser tool. Use server-side verification libraries for that.

Is my JWT token safe to paste here?

Decoding happens 100% in your browser using Base64URL string parsing — no data is transmitted to any server. That said, avoid pasting production tokens with sensitive claims in shared or public computers.

What are the common JWT claims I should check?

The most important claims are: exp (expiration time), iat (issued at), sub (subject/user ID), iss (issuer), and aud (audience). This tool displays all of them with human-readable timestamps.