JWT Decoder
Decode and inspect JSON Web Tokens instantly to view header, payload, and signature information with syntax highlighting.
Instant Decoding
Decode JWT tokens instantly with automatic parsing
Token Inspection
View header, payload, and signature separately
100% Secure
All processing happens locally - nothing stored online
Key Features
- Automatic JWT token decoding
- Syntax-highlighted JSON output
- Header information display
- Payload claims inspection
- Signature section viewing
- Expiration time detection
- Issued-at time display
- One-click copy for each section
- Token validation and error messages
- Dark mode support
What You Can View
Header
Algorithm type (HS256, RS256, etc.) and token type
Payload
User claims, permissions, and custom data
Signature
Cryptographic signature for verification
Expiration
Token expiry time with warnings for expired tokens
Issued At
When the token was originally created
User Data
Username, email, roles, and custom claims
What Is a JWT Decoder?
A JWT decoder is an online tool that allows you to inspect JSON Web Tokens (JWTs) instantly. It separates and displays the header, payload, and signature of your token with syntax highlighting, allowing you to check claims, expiration, and other important information securely and privately in your browser.
How Does the ALGODETA JWT Decoder Work?
Simply paste your JWT token into the decoder. The tool automatically parses the token and displays the header, payload, and signature sections. Expiration and issued-at times are highlighted, and any errors or invalid tokens are clearly shown. All processing happens locally, so your tokens remain private and secure.
Why Use an Online JWT Decoder?
JWT decoders are essential for developers and security professionals. Using an online decoder helps you:
- Quickly inspect token headers, payloads, and signatures
- Validate expiration times and issued-at timestamps
- Debug authentication and authorization issues
- Learn about JWT claims and structure
- Keep all sensitive token data local and secure
Key Benefits of ALGODETA JWT Decoder
- Instant Decoding: Parse JWT tokens immediately with automatic sectioning.
- Header & Payload Inspection: View algorithms, claims, and custom data.
- Signature Section: Inspect cryptographic signatures.
- Expiration Alerts: Detect expired tokens instantly.
- One-Click Copy: Copy any token section quickly.
- Secure & Private: All operations occur in your browser; no data leaves your device.
- Dark Mode Support: Comfortable decoding in any theme preference.
Who Should Use This JWT Decoder?
Ideal for:
- Developers and software engineers
- IT and security professionals
- Backend and frontend teams working with JWT authentication
- Educators and students learning web security
- Anyone needing to inspect JWT tokens safely
Common Use Cases
- Inspecting tokens during authentication debugging
- Validating token payload claims for security audits
- Checking expiration and issued-at times
- Verifying token structure and algorithm
- Educational exploration of JWT token anatomy
How to Decode a JWT Token in Seconds (Step-by-Step)
- Copy your JWT token.
- Paste it into the JWT Decoder input field.
- View the header, payload, and signature sections instantly.
- Check expiration and issued-at timestamps for validity.
- Copy any section using one-click copy buttons.
- Use the decoder for debugging or educational purposes.
Is the ALGODETA JWT Decoder Secure?
Absolutely. All decoding happens entirely in your browser. No JWT tokens are sent to any server, ensuring complete privacy and security for sensitive authentication data.
Frequently Asked Questions
Is the JWT decoder free?
Yes, completely free! No sign-up required and no limitations.
Do you store my JWT tokens?
No. All decoding happens locally in your browser. Tokens never leave your device.
Can this tool verify JWT signatures?
This tool decodes and displays JWT tokens. To verify signatures, you need the secret key, which should remain private.
What JWT algorithms are supported?
Supports standard JWT algorithms including HS256, HS384, HS512, RS256, RS384, RS512, ES256, and more.
Can I see if a token is expired?
Yes! The decoder automatically detects expiration times and shows warnings for expired tokens.
Is it safe to decode production tokens?
All processing is local, but we recommend caution with production tokens containing sensitive data.
Ready to Decode Your JWT Tokens?
Get started in seconds with our intuitive JWT decoder