Algorithm:
|
HEADER: Algorithm & Token Type
{
"alg": "HS256",
"typ": "JWT"
}PAYLOAD: Public & Private Claims
{
"sub": "1234567890",
"name": "Alex Mercer",
"role": "admin",
"iat": 1516239022
}SIGNATURE HASH
HMACSHA256(base64UrlEncode(header) + "." + base64UrlEncode(payload), secret)
Performance & Privacy Guarantee
Engineered for Modern Developers
Full Privacy Sandboxing
Secret keys and authentication tokens never leave your local browser instance.
Bidirectional Engine
Seamlessly switch between token decoding and real-time JWT token generation.
HMAC Algorithm Support
Supports standard HS256, HS384, and HS512 cryptographic signature workflows.
Payload Claims Inspector
Inspect sub, iat, exp timestamps and custom claim structures instantly.
Knowledge Base
Frequently Asked Questions
Yes. All parsing, base64url decoding, and cryptographic operations run 100% locally in your browser. No token or secret is ever sent to any remote server.
A JWT is an open RFC 7519 standard that defines a compact and self-contained way for securely transmitting information between parties as a JSON object.
A standard JWT consists of three parts separated by dots (.): Header (algorithm & token type), Payload (claims data), and Signature (verifies integrity).
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