JWT Decoder - Decode JSON Web Tokens Without Signature Verification

What This Tool Does & Key Features

• Decode JWT tokens without signature verification.
• View the decoded header and payload.
• No signature verification required.

Step-by-Step How to Use Guide

1. Paste your JWT token into the provided textarea.
2. Click the "Decode JWT" button.
3. The decoded header and payload will be displayed below.

Underlying Formula / Technical Logic

The JWT Decoder tool uses the following steps to decode a JWT:

1. Split the JWT into three parts using the dot (.) separator.
2. Base64 URL decode the first and second parts (header and payload).
3. JSON decode the decoded header and payload.

Practical Real-World Examples

Example 1

Input JWT: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c Output:

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

{ "sub": "1234567890", "name": "John Doe", "iat": 1516239022 }

Example 2

Input JWT: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyLCJleHAiOjE2MjM0NTY3ODkwfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c Output:

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

{ "sub": "1234567890", "name": "John Doe", "iat": 1516239022, "exp": 16234567890 }

Comparison or Decision Matrix / Checklist

Feature	JWT Decoder	Alternative Tools
Free	Yes	Varies
No signature verification	Yes	Varies
Easy to use	Yes	Varies

Common Mistakes & How to Avoid Them

• Mistake: Copying the entire JWT including the signature. How to Avoid: Only copy the first two parts (header and payload) separated by dots.
• Mistake: Forgetting to paste the JWT into the textarea. How to Avoid: Ensure the JWT is pasted into the provided textarea before clicking the "Decode JWT" button.