JWT Toolkit

Decode, verify, generate and analyze JSON Web Tokens online.

Browser Processing Free Forever No Signup Mobile Friendly
🔒 JWT tokens and secret keys are processed securely. Nothing is stored.

1. Decode JWT Token

Decode JWT header, payload, claims and signature information.

2. Verify JWT Signature

Verify HS256 JWT token signatures using your secret key.

3. Generate JWT Token

Create HS256 JWT tokens using JSON payload and secret key.

Continue Your Workflow

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Security Debugging Tool

Free JWT Toolkit to Decode and Analyze JSON Web Tokens

Decode JWT headers and payloads, inspect claims, review expiration values and debug authentication tokens used by APIs, SPAs and mobile apps.

JWT decoder JWT toolkit JSON Web Token JWT claims JWT analyzer

What is a JWT?

A JSON Web Token is a compact token format commonly used for authentication and authorization. It usually contains a header, payload and signature separated by dots.

Developers inspect JWTs to understand user claims, expiration times, issuer values, audience values and authentication behavior. Sensitive tokens should be handled carefully because payload data is often readable after decoding.

Key Features

Header Inspection

Read token type and signing algorithm details.

Payload Claims

Inspect user IDs, roles, issuer, audience and custom claims.

Expiration Debugging

Review token timing issues during login and API testing.

Authentication Workflow

Understand how frontend and backend systems exchange tokens.

Common Use Cases

Debug API authentication
Review JWT claims
Check token expiration
Understand bearer tokens
Test login flows
Analyze authorization payloads

How to Use This Tool

  1. 1 Paste the JWT into the toolkit.
  2. 2 Review the decoded header and payload.
  3. 3 Check expiration and claim values.
  4. 4 Use the output to debug your authentication flow.

Frequently Asked Questions

Is a decoded JWT secret?

The payload can often be read by anyone with the token. Do not put sensitive secrets in JWT payloads.

Does decoding verify the signature?

Decoding and verifying are different. Verification requires the correct secret or public key.

Can I paste production tokens?

Avoid pasting active production tokens into online tools unless your security policy allows it.