🔐 JWT Decoder Online
The JWT Decoder Tool helps you decode and analyze any JSON Web Token by extracting its header and payload in human-readable format. Instantly view token claims, expiration time, user data, and metadata without exposing your information to a server. You can also verify the token's signature using a secret key to check its authenticity. This secure JWT decoding tool is perfect for debugging, validating, and understanding JWT-based authentication flows.
Why Use Our JWT Decoder?
- 🔍 Instantly decode JWTs in your browser.
- 🧩 Verify signatures with HS256, HS384, HS512.
- 🛡️ 100% client-side, no data is uploaded.
- 💡 Perfect for debugging, testing, and learning JWT structure.
How JWT Decoding Works
A JWT consists of header, payload, and signature. The decoder parses the Base64 URL encoded segments and optionally verifies the signature with your secret key.
This process is fully client-side, fast, and secure — ideal for developers and API testing.
JWT Decoder Use Cases
- 🔹 Debug API authentication tokens
- 🔹 Inspect SSO or OAuth tokens
- 🔹 Learn JWT structure for educational purposes
- 🔹 Verify integrity of client-server communications
Frequently Asked Questions
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