Decode and inspect JWT tokens instantly in your browser. Parse header, payload, and signature with zero server round-trips.
JSON Web Tokens (JWT) are an open standard (RFC 7519) for securely transmitting information between parties as a JSON object. JWTs are commonly used for authentication and information exchange in modern web applications. This tool decodes any JWT token entirely in your browser — the token is never sent to a server, ensuring complete privacy. Simply paste your JWT to instantly view the decoded header, payload, and signature components.
A JSON Web Token (JWT) is a compact, URL-safe means of representing claims to be transferred between two parties. It consists of three parts separated by dots: a header, a payload, and a signature. JWTs are widely used for authentication in web applications and APIs.
Yes, this tool is completely safe to use. All decoding happens locally in your browser — your JWT token is never sent to any server. However, be cautious about sharing JWT tokens in general, as they may contain sensitive information.
A JWT has three parts separated by dots (.): (1) Header — contains metadata like the algorithm and token type, (2) Payload — contains the claims or data, (3) Signature — used to verify the token has not been tampered with. Only the header and payload are decoded by this tool; the signature cannot be verified without the secret key.
"exp" stands for "Expiration Time." It is a registered claim that specifies the time after which the JWT must not be accepted for processing. This tool automatically detects and warns you if a token has expired.
No, this tool only decodes the header and payload for inspection. Verifying the signature requires the secret key or public key that was used to sign the token. Signature verification should be done by your application server.
HS256 (HMAC with SHA-256) is a symmetric algorithm that uses the same secret key for signing and verification. RS256 (RSA with SHA-256) is an asymmetric algorithm that uses a private key to sign and a public key to verify. RS256 is generally preferred for distributed systems because the public key can be shared safely.