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JWT解析器
JWT令牌输入
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JWT Parser - Free Online JWT Token Decoder & Analyzer

What is JWT Parser?

JWT Parser is a powerful, free online tool designed for developers, security professionals, and system administrators who need to decode, analyze, and validate JSON Web Tokens (JWT). This comprehensive JWT decoder instantly parses JWT tokens, revealing their header, payload, and signature components in a user-friendly format.
Whether you're debugging authentication issues, analyzing token contents, or implementing JWT-based security systems, our JWT parser provides the precision and reliability needed for professional JWT token analysis. The tool supports all standard JWT algorithms and formats, making it an essential resource for anyone working with JWT-based authentication.

🚀 Key Features

Advanced JWT Decoding

  • Instant Token Parsing: Decode JWT header, payload, and signature in seconds
  • Algorithm Detection: Automatic identification of signing algorithms (HS256, RS256, ES256, etc.)
  • Claims Analysis: Detailed view of standard and custom JWT claims
  • Expiration Validation: Real-time checking of token expiration status
  • Format Verification: Comprehensive JWT structure validation

Security & Validation

  • Signature Analysis: Examine JWT signatures and signing methods
  • Timestamp Verification: Check iat (issued at), exp (expires), and nbf (not before) claims
  • Audience Validation: Verify intended token recipients (aud claim)
  • Issuer Information: Display token issuer details (iss claim)
  • Security Insights: Identify potential security concerns

Developer-Friendly Tools

  • JSON Formatting: Beautiful, syntax-highlighted JSON output
  • One-Click Copy: Easy copying of decoded components
  • Error Detection: Clear error messages for invalid tokens
  • Multiple Formats: Support for various JWT token formats
  • No Registration: Free tool with no signup required

💼 Use Cases

Authentication & Authorization

  • API Security Testing: Validate tokens used in REST API authentication
  • Login System Debugging: Analyze authentication tokens in web applications
  • OAuth Integration: Debug OAuth 2.0 and OpenID Connect tokens
  • SSO Implementation: Troubleshoot Single Sign-On token exchanges
  • Microservices Security: Validate inter-service communication tokens

Development & Testing

  • Token Generation Testing: Verify tokens created by your applications
  • Claims Validation: Ensure proper JWT claims implementation
  • Security Auditing: Review token security and best practices
  • Integration Testing: Test JWT token handling in various scenarios

📋 How to Use JWT Parser

Step 1: Access the Tool

Open your web browser and navigate to our free JWT Parser tool. No registration or installation required.

Step 2: Input Your JWT Token

Paste your JWT token into the input field. JWT tokens typically start with "eyJ" and consist of three parts separated by dots (.).

Step 3: Automatic Parsing

The tool automatically decodes your JWT token and displays:
  • Header: Algorithm and token type information
  • Payload: Claims and user data
  • Signature: Signature verification details

Step 4: Analyze Results

Review the parsed information including:
  • Token expiration status
  • Issuer and audience details
  • Custom claims and metadata
  • Security recommendations

Step 5: Copy or Export

Use the copy functions to extract specific components or save the entire analysis for your development workflow.

🔧 Technical Specifications

Supported Algorithms

  • HMAC: HS256, HS384, HS512
  • RSA: RS256, RS384, RS512
  • ECDSA: ES256, ES384, ES512
  • PSS: PS256, PS384, PS512

Standard Claims Support

  • iss (Issuer): Token issuer identification
  • sub (Subject): Token subject identification
  • aud (Audience): Intended token recipients
  • exp (Expiration): Token expiration timestamp
  • nbf (Not Before): Token validity start time
  • iat (Issued At): Token issuance timestamp
  • jti (JWT ID): Unique token identifier

🛡️ Security & Privacy

Data Protection

  • Client-Side Processing: All JWT parsing happens in your browser
  • No Data Storage: We don't store or log your JWT tokens
  • Privacy First: Your sensitive information never leaves your device
  • Secure Connection: HTTPS encryption for all communications

Best Practices

  • Always validate JWT signatures in production
  • Use strong, unique secrets for HMAC algorithms
  • Implement proper token expiration policies
  • Regularly rotate signing keys
  • Monitor for token misuse and anomalies

❓ Frequently Asked Questions

Is this JWT parser free to use?

Yes, our JWT parser is completely free with no limitations or registration requirements.

Can I use this tool for production tokens?

While the tool is secure and processes data locally, we recommend using it primarily for development and testing purposes.

What JWT algorithms are supported?

We support all standard JWT algorithms including HMAC, RSA, ECDSA, and PSS variants.

How do I validate JWT signatures?

The tool can analyze signatures, but for security validation, you'll need to provide the appropriate secret or public key.

Can I parse expired JWT tokens?

Yes, you can decode expired tokens. The tool will clearly indicate the expiration status.

🌟 Why Choose Our JWT Parser?

  • Fast & Reliable: Instant JWT token decoding with accurate results
  • User-Friendly: Intuitive interface designed for developers
  • Comprehensive: Complete JWT analysis with detailed insights
  • Secure: Client-side processing ensures data privacy
  • Free: No cost, no registration, no limitations
  • Updated: Regular updates to support latest JWT standards

Start using our JWT Parser today to streamline your JWT token analysis and debugging workflow!