Description

JWT.io is an essential development tool for working with JSON Web Tokens, providing instant decoding of JWT headers, payloads, and signatures. The interface displays parsed token components in a human-readable tree view, with color-coded validation for expired/malformed tokens. Developers can verify signatures against public keys (supports RS256, HS256, etc.) and test token generation with custom claims. While not a token generator itself, it's invaluable for debugging authentication flows in APIs and web apps. The tool processes all data client-side for security, with no token data transmitted to servers. Open-source libraries are available for integration into development pipelines. Essential for backend engineers, security auditors, and anyone implementing OAuth 2.0 or OpenID Connect protocols.

Screenshots

Screenshot 1 of JWT.io