JWT Encode/Decode Tool

JWT Encoder/Decoder is a professional online tool for parsing, validating, and generating JSON Web Tokens, supporting both HMAC and RSA signature algorithms. It helps backend developers, API designers, security engineers, and authentication system developers quickly debug and process JWT tokens. The tool offers two operation modes: Decode mode parses JWT strings, automatically extracting header and payload content while verifying signature validity; Encode mode allows custom header and payload input, accepting shared secrets or PEM-format private/public keys to generate compliant JWT tokens with one click. In everyday development, JWT is widely used for user authentication, API authorization, single sign-on, and more, but manually constructing or parsing JWT tokens involves Base64Url encoding and signature calculations—a tedious and error-prone process. With an intuitive interface, users simply paste a token or fill in parameters to get clear parsing results or generate new tokens. The signature verification feature helps quickly identify whether a token has been tampered with or expired. The tool also supports key pair generation, making it easy for developers to obtain RSA keys in test environments. Whether debugging OAuth2.0 flows, verifying tokens returned by APIs, or generating authentication credentials for microservices architectures, JWT Encoder/Decoder provides efficient and reliable support, making it an essential tool in modern web development and security protection.