JWT Decoder

Decode JSON Web Tokens (JWT) payload, header, and signature securely in your browser.

How to Use JWT Decoder

  1. Paste a full JWT (three dot-separated parts) into the input box.
  2. The tool automatically splits and decodes the header and payload sections into readable JSON.
  3. Review the decoded claims - expiry (`exp`), issuer, and any custom fields - directly in the output panes.

Key Features & Practical Use Cases

  • Decoding web tokens securely in your browser to verify authentication claims and payload claims.
  • Inspecting encryption algorithms or signature header metadata without uploading tokens.
  • Debugging user access permissions and token lifespan limits during code builds.

Frequently Asked Questions

Does this verify the token's signature?

No - it only decodes the header and payload (which are just Base64URL-encoded, not encrypted); it does not check the signature against a secret or public key.

Is my token sent anywhere?

No - decoding happens entirely in your browser using standard Base64URL decoding, so the token never leaves your device.

Can I decode an expired token?

Yes - it will still show you the decoded payload including the `exp` timestamp, so you can confirm exactly when (or if) it expired.

About OneClickly

OneClickly offers 100+ premium online tools for PDF operations, image compression and conversion, text utilities, calculators, and developer tools. All tools run 100% in your browser - no file uploads, no data collection, maximum privacy guaranteed.

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