JWT Decoder & Encoder
Decode, inspect, and encode JSON Web Tokens JWT. Visualize header, payload, and verify signature structure securely in browser.
JWT Decoder
What is JWT Decoder & Encoder?
JWT Decoder & Encoder is a security-focused developer tool for working with JSON Web Tokens JWT the open standard RFC 7519 for securely transmitting information between parties as digitally signed JSON objects. JWTs are ubiquitous in modern authentication OAuth2 access tokens OpenID Connect ID tokens API session tokens and microservice-to-microservice communication all rely heavily on JWT format. A JWT consists of three Base64URL-encoded sections separated by dots the header algorithm and token type the payload claims including issued-at expiration user ID roles and the cryptographic signature. This decoder splits the token pretty-prints the JSON header and payload with color-coded claims highlights expiration status with timing warnings and supports HMAC HS256 HS384 HS512 and RSA RS256 RS384 RS512 signature verification when you provide the secret key or public key. Never paste production tokens containing sensitive data into untrusted tools this JWT decoder performs one hundred percent of its parsing and verification locally in your browser.
When to Use JWT Decoder & Encoder
Use when debugging authentication flows, inspecting access token claims, checking token expiration times, verifying signature validity, or encoding test JWTs for API development.
How to Use JWT Decoder & Encoder
Paste a JWT token to decode and inspect header, payload, signature sections. To verify or encode, enter your signing key and select algorithm. Results update automatically with expiry status.
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