JWT Encoder/Decoder

JWT Tool - Advanced Encoder/Decoder Extension Overview: A powerful developer tool for inspecting, validating, and manipulating JSON Web Tokens directly in your browser. This extension provides complete JWT handling capabilities with robust security features. Key Features: Instant Decoding: Break down JWT tokens into header, payload, and signature components Smart Validation: Automatic checks for expiration, validity periods, and issuance dates Realtime Encoding: Generate new tokens with multiple algorithm support (HS256/384/512, RS256/384/512, ES256/384/512,none) Signature Verification: Validate token signatures against provided keys Secure Handling: All processing occurs locally - no token data leaves your browser Developer-Friendly: Clean interface with syntax-highlighted JSON views Technical Specifications: Supports all standard JWT algorithms (HMAC, RSA, ECDSA) Clipboard integration for easy token pasting/copying Comprehensive token validation including: Expiration (exp) Not Before (nbf) Issued At (iat) Manifest v3 compliant Zero external dependencies (except jsrsasign library bundled locally) Security Notice: This tool is designed for development purposes only. We strongly recommend: Never using production secrets Always working in secure environments Verifying tokens contain no sensitive data before processing Ideal For: API developers Security researchers Quality assurance testers Authentication system debuggers