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CompressNConvert

JWT Workbench

Decode JWTs, inspect registered claims, verify HMAC signatures, and generate local development tokens.

Runs locally in your browser

Header

{ "alg": "HS256", "typ": "JWT" }

Payload

{ "sub": "1234567890", "name": "Ada Lovelace", "iat": 1516239022 }
  • • No expiration (exp) claim is present.

Complete tool guide

JWT Workbench guide

A JSON Web Token contains a protected header, claims payload, and signature. Decoding reveals claims but does not prove authenticity; verification does.

Your input is processed in the current browser tab and is not sent to the application server.

Why use this tool?

  • Inspect or transform developer data without installing another utility.
  • Copy a clean result directly into code, a terminal, an API client, or documentation.
  • Keep routine developer work in one fast, consistent interface.

Common use cases

  • Debugging authentication claims
  • Verifying an HS256/384/512 test token
  • Generating local integration fixtures

How to use it

  1. 1

    Choose Decode, Verify, or Generate.

  2. 2

    Paste a token or JSON payload.

  3. 3

    Supply the expected algorithm and secret when signing or verifying.

  4. 4

    Review claims and warnings before using the result.

Decode versus verify

Anyone can decode a JWT payload. Trust it only after verifying its signature and required claims against the expected issuer and audience.

Local HMAC scope

This workbench supports shared-secret HS256, HS384, and HS512 workflows without contacting a JWKS endpoint.

Secret handling

The secret remains in the browser tab, but should still be cleared on shared devices and never copied into logs.

Practical tips for better results

  • Do not accept the algorithm from an untrusted token without an allowlist.
  • Require expiration, issuer, and audience in production.
  • Use short-lived development tokens and non-production secrets.

Frequently asked questions

Does the JWT Workbench upload my data?

No. The transformation runs locally in your browser. Avoid pasting secrets into any tool you do not control, and clear the fields when using a shared device.

Can I use the result in production?

You can copy or download the result, but review it in the context of your application and run the project-specific tests or validation required by your workflow.

Keep working

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