🔐
generator
Password Generator
Generate strong, secure random passwords with customizable length and character types.
password generator
Use Tool → 🔓
checker
JWT Decoder
Decode JWT headers and payloads, inspect token claims, and review signature bytes without sending data anywhere.
jwt decoderjwt parserjson web token decoderjwt debugger
This tool only DECODES tokens. It does not verify signatures.
Paste a JWT to inspect its header, payload, and signature bytes.
Token parts
header.payload.signature
Encoded token segments will appear here.
exp
—
iat
—
sub
—
iss
—
Header
Part 1Decoded header JSON will appear here.
Payload
Part 2Decoded payload JSON will appear here.
Signature
Part 3Decoded signature hex will appear here.
How to use
How to inspect JWT headers, claims, and signature bytes safely in the browser
- 1 Paste the full token into the input area so the tool can split the header, payload, and signature segments.
- 2 Decode the token to view the parsed JSON for the header and payload without sending anything to a server.
- 3 Review highlighted claims such as exp, iat, sub, and iss to understand expiration, issue time, subject, and issuer details quickly.
- 4 Check the signature panel if you want to inspect the raw bytes in hexadecimal form for debugging or comparison work.
- 5 Copy the decoded payload when you need to share claim data internally, but remember the tool does not verify whether the token is actually trustworthy.
JWTs show up everywhere in modern authentication systems, but they are difficult to inspect by eye because each section is compact Base64URL text. A decoder makes the contents readable immediately, which is helpful when you are debugging login flows, checking claim names, comparing environments, or confirming whether an exp timestamp matches what your backend issued. Because the page runs fully client-side, it is convenient for quick analysis during development or support work.
It is important to separate decoding from verification. Anyone can decode a JWT payload, but that does not prove the token was signed by a trusted issuer or that it has not been tampered with. This tool is best used for inspection: reading claims, looking at header metadata, and checking whether a token appears expired. Signature validation should still happen in the system that owns the secret key or public-key verification process.
Related tools