JWT Decoder Online — Decode JSON Web Tokens
Free online JWT decoder. Paste a JSON Web Token to instantly see its header, payload, and signature. No verification — just inspection.
JWT Token
Header
Payload
Signature
💡 What is this
JWT Decoder
- JSON Web Tokens (JWTs) are compact tokens used for authentication.
- This tool decodes the three parts — header (algorithm), payload (claims), and signature — so you can inspect them without verification.
📖 How to use
Step by Step
- Paste a JWT token (starts with eyJ...)
- Click Decode to see header & payload
- Timestamps (iat, exp, nbf) are auto-converted to dates
- The signature is shown as a hex string
🎯 Use cases
When to use
- Debugging authentication flows
- Inspecting token claims and expiry
- Verifying token structure before sending
- Checking algorithm and issuer fields
Frequently Asked Questions
Does this verify the JWT signature?▾
No. This tool only decodes and displays the token contents. Signature verification requires the secret key or public key, which should never be shared in a browser tool.
Is it safe to paste my JWT here?▾
Yes. Everything runs locally in your browser. The token is never sent anywhere. However, avoid sharing JWTs from production systems publicly.
What are iat, exp, and nbf?▾
These are standard JWT claims: iat (issued at), exp (expiration time), and nbf (not before). They are Unix timestamps that this tool auto-converts to human-readable dates.