JWT Decoder
Decode and inspect JSON Web Tokens. View the header, payload, signature, algorithm, and expiration. All processing happens locally in your browser — tokens never leave your device.
{
"alg": "HS256",
"typ": "JWT"
}{
"sub": "user_123",
"name": "Jane Doe",
"iat": 1715000000,
"exp": 1746536000,
"roles": [
"admin"
]
}qpnHh0V2nB3a3vK5V6Kmdf_wS8B7g4m4kYvN3mYX0QkThe signature is a cryptographic hash — it cannot be verified without the secret or public key used to sign the token. This tool only decodes the contents.
About JSON Web Tokens
A JSON Web Token (JWT) is a compact, URL-safe way to represent claims between two parties. It consists of three base64url-encoded segments joined by dots: a header describing the algorithm, a payload with the claims, and a signature used to verify authenticity.
Because the payload is only encoded — not encrypted — anyone with the token can read its contents. Never include sensitive data in the payload and always verify the signature on the server with the correct secret or public key.