Professional JWT Encoder & Decoder
Encode, decode, and validate JSON Web Tokens with real-time processing
JWT Algorithm Support
Comprehensive support for all major JWT signing algorithms with security recommendations
HMAC
SymmetricHash-based Message Authentication Code using shared secret
Algorithms:
Common Use Cases:
- Internal APIs
- Microservices
- Simple authentication
RSA
AsymmetricRSA digital signatures with PKCS#1 padding
Algorithms:
Common Use Cases:
- Public APIs
- Cross-domain auth
- Enterprise systems
ECDSA
AsymmetricElliptic Curve Digital Signature Algorithm
Algorithms:
Common Use Cases:
- Mobile apps
- IoT devices
- Modern web services
RSA-PSS
AsymmetricRSA signatures with Probabilistic Signature Scheme
Algorithms:
Common Use Cases:
- High-security applications
- Government systems
Professional JWT Token Management
Advanced JWT tools for developers, security engineers, and API architects
JWT Token Decoder
Decode JWT tokens to extract header, payload claims, and signature information with comprehensive validation
JWT Token Encoder
Create custom JWT tokens with configurable headers, claims, and multiple signing algorithms
Multi-Algorithm Support
Support for HMAC (HS256/384/512), RSA (RS256/384/512), ECDSA (ES256/384/512), and RSA-PSS (PS256/384/512)
Expiration Validation
Automatic expiration checking with time-to-expiry calculations and renewal recommendations
Claims Extraction
Parse and display all standard and custom JWT claims with type validation and formatting
Token Validation
Comprehensive structure validation with detailed error reporting and security recommendations
Header Analysis
Extract and analyze JWT headers including algorithm verification and key ID information
Real-time Processing
Instant encoding and decoding with live validation feedback and performance metrics
Developer Tools
Copy tokens and claims, generate sample tokens, and export validation results for debugging
Enterprise JWT Use Cases
Real-world applications of JWT tokens in modern authentication and authorization
API Authentication & Authorization
Secure API endpoints with token-based authentication and fine-grained authorization
Applications:
- REST API access tokens
- Microservices authentication
- Rate limiting and throttling
- Service-to-service communication
Recommended Algorithms:
Single Sign-On (SSO)
Enable seamless user experience across multiple applications with centralized authentication
Applications:
- Enterprise identity management
- Cross-application authentication
- SAML and OIDC integration
- Multi-tenant applications
Recommended Algorithms:
OAuth 2.0 & OpenID Connect
Implement secure authorization flows with industry-standard OAuth and OpenID protocols
Applications:
- Third-party application access
- Social media integrations
- Identity provider integration
- Consent management
Recommended Algorithms:
Mobile & Web Applications
Secure mobile and web applications with efficient token-based authentication
Applications:
- Mobile app authentication
- Progressive web apps (PWA)
- Session management
- Offline token validation
Recommended Algorithms:
JWT Security Best Practices
Essential security guidelines for implementing JWT tokens in production
Choose Strong Algorithms
CriticalUse RS256, ES256, or PS256 for production systems. Avoid HS256 for public-facing APIs where key distribution is challenging.
Implement Token Expiration
CriticalAlways set reasonable expiration times (exp claim) and implement refresh token mechanisms for long-lived sessions.
Validate All Claims
HighVerify issuer (iss), audience (aud), and expiration (exp) claims on every token validation request.
Secure Key Management
CriticalUse proper key rotation, secure key storage (HSM/KMS), and never expose private keys in client-side code.
Implement Rate Limiting
HighApply rate limiting to token endpoints to prevent brute force attacks and token enumeration.
Use HTTPS Only
CriticalAlways transmit JWT tokens over HTTPS to prevent token interception and man-in-the-middle attacks.
Standard JWT Claims Reference
Complete reference for standard JWT claims and their usage
Claim | Name | Type | Description | Required |
---|---|---|---|---|
iss | Issuer | string | Identifies the principal that issued the JWT token | Required |
sub | Subject | string | Identifies the principal that is the subject of the JWT | Optional |
aud | Audience | string | array | Identifies the recipients that the JWT is intended for | Required |
exp | Expiration Time | number | Identifies the expiration time after which the JWT MUST NOT be accepted | Required |
nbf | Not Before | number | Identifies the time before which the JWT MUST NOT be accepted | Optional |
iat | Issued At | number | Identifies the time at which the JWT was issued | Optional |
jti | JWT ID | string | Provides a unique identifier for the JWT | Optional |
Frequently Asked Questions
Common questions about JWT tokens and authentication
What is a JWT token and how does it work?
JWT (JSON Web Token) is a compact, URL-safe means of representing claims between two parties. It consists of three Base64URL-encoded parts: header, payload, and signature, separated by dots. JWTs are commonly used for authentication and authorization in web applications and APIs.
Which JWT algorithm should I use for my application?
For production systems, use asymmetric algorithms like RS256, ES256, or PS256. These provide better security for public-facing APIs. Use HS256 only for internal systems where you can securely share the secret key between all parties.
How do I validate JWT token expiration?
Check the 'exp' claim in the JWT payload against the current Unix timestamp. If the current time is greater than the exp value, the token is expired and should be rejected. Always implement proper token refresh mechanisms for long-lived sessions.
Is this JWT tool secure for production tokens?
Our JWT tool processes all tokens locally in your browser without transmitting data to our servers. However, never paste production secrets or sensitive tokens into any online tool. Use this tool for development, testing, and learning purposes only.
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