100% Private
All decoding happens in your browser using JavaScript. Your tokens and sensitive claims never leave your device.
Browser tool● Processed in your browser
JWT Decoder
Paste a JSON Web Token to instantly decode and inspect its header, payload, and signature. Check expiration status, view all claims, and copy individual sections. Everything runs in your browser.
Paste a JWT token above to decode it, or click Sample JWT to try it out.
01 · Guide
How it works
- 01
Paste your JWT token into the input field, or click 'Sample JWT' to load an example token
- 02
The token is decoded in real-time as you type, showing the Header, Payload, and Signature sections
- 03
Check the expiration status to see if the token is still valid or has expired
- 04
Click the copy button on any section to copy the decoded JSON to your clipboard
Why use this tool
Real-Time Decoding
The token is decoded instantly as you paste or type. No need to click a button — results appear immediately.
Expiration Check
Automatically detects the exp claim and shows whether the token is still valid or has expired, with relative time display.
Color-Coded Sections
Header, Payload, and Signature are displayed in distinct color-coded sections for easy visual inspection.
Frequently asked questions
Is my JWT token sent to a server?+
No. All decoding happens entirely in your browser using JavaScript. Your token and its claims never leave your device.
What is a JSON Web Token (JWT)?+
A JWT is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three Base64URL-encoded parts separated by dots: a header, a payload with claims, and a signature.
Can this tool verify the JWT signature?+
This tool decodes and displays the signature, but does not verify it. Signature verification requires the secret key or public key, which should never be shared in a browser tool.
What claims can I see in the payload?+
You can see all standard claims such as sub (subject), iat (issued at), exp (expiration), iss (issuer), aud (audience), and any custom claims included in the token.
Does it support expired tokens?+
Yes. The tool decodes any valid JWT regardless of its expiration status. It also clearly shows whether the token has expired and how long ago.
04 · More tools
View all tools →