JWT Decoder

Decode JWT tokens to view header, payload, and check expiration

Free to use
Security

About JWT Decoder

JWT Decoder is a fast, privacy-focused tool for decoding JSON Web Tokens to inspect their structure and contents. Whether you are debugging authentication issues, validating token claims, or analyzing security tokens, this tool gives you instant visibility into what is inside your JWTs without sending data to external servers.

Perfect for developers, security teams, and API integrators who need to quickly verify token composition, check expiration times, and inspect claims. All processing happens locally in your browser, ensuring your sensitive tokens never leave your device.

100% Local
No data sent anywhere
Instant
Decode in milliseconds
3 sections
Header, Payload, Signature
Expiry check
Automatic validation

How to use JWT Decoder

01

Paste Your JWT

Enter or paste your complete JWT token into the input field. The token should be in the standard format with three base64-encoded sections separated by dots.

02

Automatic Decoding

The tool instantly decodes and displays the header, payload, and signature with full JSON formatting and readable timestamps.

03

Review & Copy Results

Inspect claims, check expiration status, and copy any decoded values or sections you need for further use.

Pro Tips

  • Check the expiration time immediately after decoding-if it shows red/expired, the token is no longer valid and will not authenticate.
  • Use the payload section to verify custom claims your application relies on, ensuring they match expected values.
  • Copy individual claim values to compare them across multiple tokens or paste into logs for debugging authentication flows.
  • Bookmark this tool for quick reference during API development-decode tokens to understand claim structure before writing validation logic.

Key features of JWT Decoder

Header & Payload Inspection

View decoded header and payload sections with formatted JSON for easy reading.

Expiration Status

Automatically detect and display token expiration time with visual status indicator.

Claim Verification

Review all JWT claims including iss, sub, aud, iat, exp, and custom claims.

Signature Display

View the complete signature and algorithm used for token verification.

One-Click Copy

Quickly copy decoded sections, claims, or raw values to clipboard.

Error Detection

Identify malformed tokens and invalid JWT structures with clear error messages.