JWT Decoder

Overview of jwt-decoder

jwt-decoder is a versatile web tool designed to decode and validate JSON Web Tokens (JWT). JWTs are widely used in web applications for securely transmitting information between parties as a JSON object. This tool simplifies the process of inspecting and understanding the contents of a JWT, making it an invaluable resource for developers, security professionals, and anyone involved in web development. With jwt-decoder, you can easily decode the header, payload, and signature of a JWT, and validate its integrity and expiration, ensuring that the token is authentic and has not been tampered with.

How to Use jwt-decoder

Step-by-Step Guide

1. Navigate to the jwt-decoder Website:

2. Open your web browser and go to the official jwt-decoder website.

3. Enter the JWT:

4. Locate the input field where you can paste your JWT. A JWT typically looks like a long string of characters divided into three parts separated by dots (e.g., eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c).

5. Decode the JWT:

6. Click the "Decode" button. The tool will then break down the JWT into its three components: Header, Payload, and Signature.

7. Review the Results:

8. The decoded information will be displayed in a structured format, allowing you to easily inspect the contents of the token. You can view the algorithm used, the expiration time, the subject, and other claims.

9. Validate the JWT:

10. If you have the secret key used to sign the token, you can enter it in the provided field and click "Validate" to check the token's integrity and expiration.

Advanced Usage

• Batch Decoding:

• For multiple JWTs, use the batch decoding feature by pasting multiple tokens separated by new lines or commas.

• Custom Claims:

• You can also inspect custom claims within the payload by expanding the JSON output.

• Token Expiration:

• The tool will highlight if the token has expired, providing a clear indication of the token's validity.

Usage Examples

Example 1: Decoding a JWT

Input:

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Output:

{
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "iat": 1516239022
  },
  "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}

Example 2: Validating a JWT with a Secret Key

Input:

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Secret Key:

your-secret-key

Output:

Token is valid.

Example 3: Inspecting Custom Claims

Input:

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyLCJyb2xlIjpbInVzZXIiLCJhZG1pbiJdfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Output:

{
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "iat": 1516239022,
    "role": ["user", "admin"]
  },
  "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}

Feature Table

Overview of jwt-decoder

jwt-decoder is a versatile web tool designed to decode JSON Web Tokens (JWTs) quickly and efficiently. JWTs are a compact, URL-safe means of representing claims to be transferred between two parties. They are widely used in web applications for authentication and authorization processes. However, understanding the contents of a JWT can be challenging without the right tool. jwt-decoder simplifies this process by breaking down the token into its constituent parts: the header, payload, and signature. This tool is invaluable for developers and security professionals who need to inspect and validate JWTs during development, testing, and troubleshooting.

How to Use jwt-decoder

Step-by-Step Guide

1. Navigate to the jwt-decoder Website: Open your web browser and go to the official jwt-decoder website.
2. Enter the JWT: In the main input field, paste the JWT you want to decode. Ensure the token is in the correct format.
3. Click Decode: Click the "Decode" button to process the token.
4. View the Results: The tool will display the decoded header, payload, and signature in separate sections. Each section provides a clear and detailed breakdown of the data.

Additional Options

• Verify Signature: If you have the secret key, you can enter it in the "Secret Key" field to verify the token's signature.
• Pretty Print: Use the "Pretty Print" option to format the JSON output for better readability.
• Download: Click the "Download" button to save the decoded token as a JSON file.

Usage Examples

Example 1: Basic Decoding

Input

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Output

{
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "iat": 1516239022
  },
  "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}

Example 2: Signature Verification

Input

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Secret Key

your-256-bit-secret

Output

{
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "iat": 1516239022
  },
  "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c",
  "verified": true
}

Example 3: Pretty Print

Input

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyLCJyb2xlcyI6WyJhZG1pbiJdfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Output (Pretty Print)

{
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "iat": 1516239022,
    "roles": ["admin"]
  },
  "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}

Feature Table