Agent X Alpha

JWT Decoder & Secret Generator

Client-SideOffline Ready

Decode JSON Web Tokens instantly to inspect payloads and headers, and generate cryptographically secure signing secrets.

Quick Presets:

Token Composition

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c3JfOTQ4MmY3MWEiLCJuYW1lIjoiQWxleCBNZXJjZXIiLCJlbWFpbCI6ImFsZXhAYWdlbnR4YWxwaGEuY29tIiwicm9sZSI6ImFkbWluIiwicGVybWlzc2lvbnMiOlsidXNlcnM6cmVhZGFsbCIsInVzZXJzOndyaXRlIiwiYXBpOmFjY2VzcyJdLCJpYXQiOjE3MjcwMDAwMDAsImV4cCI6MjUyNDYwODAwMH0.2WpIqG9J1U_xQZlVj-7mRj4F8BwPn6z3HlD4t0uKnEw
Runs 100% locally in your browser. Tokens never leave your device.
Header — Algorithm & Token Type
// Waiting for token...
Payload — Claims & Identity Data
// Waiting for claims...
Signature — Cryptographic Checksum
// Waiting for signature...

Cryptographic Secret Generator

Generate secure random keys with high entropy to sign HS256, HS384, or HS512 JWTs.

100% Client-Side Privacy

Your JWT tokens and session credentials never leave your browser. All decoding, claim parsing, and HMAC calculations run on-device.

Automated Expiry Checks

Instantly see whether your authentication token is active or expired, with human-readable relative countdowns and exact UTC timestamps.

HMAC Signature Verification

Simulate signature validation using native Web Crypto API to guarantee your signing keys correctly generate authentic tokens.

Frequently Asked Questions

Is it safe to paste confidential production JWTs into this decoder?
Yes. AgentXAlpha decodes JSON Web Tokens purely client-side by Base64URL-decoding the header and payload segments directly in your browser. Tokens are never transmitted to our servers or stored in any database.
Can this tool verify JWT digital signatures?
The decoder parses and visually explains the header algorithm and payload claims (e.g. exp, iat, sub, iss) and checks timestamp validity. Secret keys can also be generated for HMAC signing.
How does the expiration (exp) audit work?
The tool parses the exp timestamp claim, compares it against the local system clock in real time, and indicates whether the token is currently valid or expired with a human-readable countdown.
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