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JWT Decoder

Decode JWT header and payload data into a readable format for quick inspection.

Tool

Use this JWT decoder to inspect the readable parts of a JSON Web Token directly in the browser. It is useful for authentication debugging, API integration checks, reading claims, checking expiry fields, and understanding token contents without manually decoding the Base64URL parts yourself.

About this tool

Use this JWT decoder to inspect the readable parts of a JSON Web Token directly in the browser. It is useful for authentication debugging, API integration checks, reading claims, checking expiry fields, and understanding token contents without manually decoding the Base64URL parts yourself.

Use jwt decoder when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.

Learn more

Why use this tool

How to use

  1. Paste the full JWT into the input box.
  2. Run the tool to decode the token parts.
  3. Review the header and payload output.
  4. Copy the decoded content if you need it for debugging or documentation.

Examples

Example

Input

eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjMifQ.signature

Output

Decoded header and payload

Shows the readable JWT sections without verifying the signature.

Example

Input

A copied auth token from an API test

Output

Readable claims and token metadata

Useful for quick auth troubleshooting.

Common errors

The user expects the signature to be verified automatically.

Fix: Remember that decoding is not the same as signature verification.

The token is incomplete or pasted with missing sections.

Fix: Paste the full JWT including all dot-separated parts.

The token contains malformed Base64URL content.

Fix: Check whether the token was copied fully and correctly.

FAQ

What does a JWT decoder do?

It decodes the readable parts of a JSON Web Token such as the header and payload.

Does decoding verify the token?

No. Decoding only reads the token content and does not verify the signature.

Why is JWT decoding useful?

It helps inspect claims, expiry data, and token structure during debugging.

Is this JWT decoder free to use?

Yes. It works online in the browser.

What is the difference between decoding and verifying a JWT?

Decoding shows readable content, while verification checks whether the signature is valid.

Use cases

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