ToolzyLab
Decode, verify, compare, search, inspect, and generate JWTs in one professional ToolzyLab tool. Supports HS256 secret verification, RS256 public-key verification, live expiry countdown, claim search, raw-vs-decoded viewer, token compare, file paste support, and JWT generation.
Paste a token, verify it, compare two tokens, search claims, inspect timestamps, or generate a fresh JWT without hopping across multiple websites.
Big upgrade with tabs, verification, compare mode, file input, and generator mode.
Header, payload, and signature segments.
Real-time countdown based on exp claim.
Side-by-side raw segments and decoded JSON.
Searchable readable explanations for common claims.
Main technical details.
| Field | Value |
|---|
HS256 or RS256 verification outcome.
Structure, expiry, warnings, and practical checks.
Complete parsed object ready for dev work.
Recent decoded tokens saved only in this browser.
A JWT header and payload are Base64url-encoded and usually readable; decoding alone does not verify origin or integrity. Paste only a safe sample, choose decode, verify, compare, or generator mode, then inspect algorithm, signature, issuer, audience, expiry, not-before time, key type, and application policy before trusting any claim.
Anyone can create a header and payload. Verification checks the cryptographic signature with the correct shared secret or public key, but the application must also restrict allowed algorithms. Never accept alg none or switch key types based only on an untrusted header.
A valid signature does not mean a token was issued for this service or is currently usable. Validate iss and aud against configured values, allow only controlled clock skew for exp and nbf, and apply revocation, session, scope, and subject rules. Displayed timestamps should be checked in UTC.
JWTs can contain personal data, roles, identifiers, and bearer access. A decoded payload is not encrypted. Use local development samples, redact reports, and verify production tokens within approved observability or server tooling. HS256 shares one secret; RS256 verification uses a public key while signing requires the private key.
A token is acceptable only when cryptography and application policy both succeed.
Technical references: RFC 7519 JSON Web Token
No. Decoding only reveals the JSON segments. Verification requires the correct key, accepted algorithm, and successful signature check, followed by claim validation.
A normal signed JWT is not encrypted; its payload can be decoded by anyone who has the token. Do not place secrets in claims.
HS256 uses a shared secret for signing and verification. RS256 uses a private key to sign and a public key to verify. Key handling and trust models differ.
exp is the time after which the token must not be accepted, while nbf is the time before which it must not be accepted. Validate timestamps with controlled clock skew.
Yes. The token can have the wrong issuer or audience, be expired, lack required scope, reference a revoked session, or violate application policy.
Avoid it. Bearer tokens can grant access and payloads may contain personal data. Use approved local or server-side tooling and safe samples.