JWT Decoder

Decode JWT header and payload sections without verifying the signature.

How to use JWT Decoder

Paste a JWT to decode its header and payload. This tool does not verify authenticity or signature validity. Start with a small known input, run the operation, and compare the result with the format expected by the system you are working with.

What this developer tool does

Decode JWT header and payload sections without verifying the signature. It is intended for debugging, prototyping, inspection, and everyday development tasks where a quick local transformation is useful.

When this tool is useful

Use JWT Decoder during debugging, prototyping, data inspection, test preparation, or small format conversions. It is designed for quick checks in the browser, while production systems should still rely on tested application code and the relevant technical specification.

How it works

The tool splits a JSON Web Token into its Base64URL-encoded header and payload sections and decodes those sections for inspection. It does not verify the token signature.

Practical example

For example, paste a JWT from a test environment to inspect claims such as issuer, audience, or expiration while debugging.

Developer notes

  • Decoding a JWT does not prove that it is authentic or trustworthy.
  • Do not paste sensitive production tokens into tools on untrusted devices.
  • Signature verification requires the appropriate algorithm and trusted key material.