Decode a sample JWT
token = eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ0ZXN0Iiwic3ViIjoidXNlcjEyMyIsImV4cCI6OTk5OTk5OTk5OSwiaWF0IjoxNzAwMDAwMDAwfQ.test
Result: Header and payload decoded.
JWT Decoder
Decode a JWT to see its header, payload, and signature. All decoding happens in your browser - the token is never sent to any server. Note: decoding does NOT verify the signature. A decoded token should not be treated as trustworthy without signature verification.
Privacy: this tool processes your data entirely in your browser. Nothing you paste or type is sent to the server.
Enter your values and press Calculate — the result appears here.
Worked examples
Frequently asked questions
Does decoding verify the signature?
No. Decoding only extracts and Base64URL-decodes the header and payload. To verify authenticity, you need the issuer's public key or secret and must verify the signature separately.
Is it safe to paste a JWT here?
Yes. All decoding happens in your browser using JavaScript. The token is never sent to our servers. However, if you suspect the token is sensitive, use an incognito/private window.
What are the three parts of a JWT?
A JWT has three Base64URL-encoded segments separated by dots: Header (algorithm and type), Payload (claims/data), and Signature (for verification).
📚 Learn More
Cybersecurity
JWT Explained: Header, Payload and Signature
Key Takeaway --> A JWT is three Base64URL-encoded parts separated by dots: header (algorithm), pay…
CybersecurityOAuth 2.0 Explained for Beginners
Key Takeaway --> OAuth 2.0 is an authorization framework — it lets users grant third-party apps li…
CybersecurityWhat Is LM Studio?
LM Studio is a desktop application that makes local AI as easy as downloading an app. Browse models…
CybersecurityCross-Site Scripting Explained for Web Developers
KEY TAKEAWAY Cross-Site Scripting (XSS) happens when untrusted user input is included in web page…
CybersecurityAPI Authentication Methods Compared
Key Takeaway --> There is no single "best" API authentication method. API keys are simple but weak…
CybersecurityHashing vs Encryption vs Encoding: What's the Difference?
Key Takeaway --> Hashing verifies integrity and stores passwords safely. Encryption keeps data con…
🔧 Related Tools
JWT Header Decoder
Decode the header segment of a JSON Web Token.
Try it now →JWT Payload Decoder
Decode the payload segment of a JSON Web Token.
Try it now →JWT Claims Viewer
View and analyze JWT claims with explanations and security warnings.
Try it now →AES-256-GCM Decrypt
Decrypt AES-256-GCM ciphertext with authentication verification.
Try it now →💬 Discuss on BestWordz Community
Join the conversation about Cybersecurity, jwt decoder, json web token on the BestWordz Community forum.
Visit Forum →💬 Discuss JWT Decoder
Have questions about JWT Decoder? Join the BestWordz Community.
Copied!