JWT Decoder
Decode any JWT (JSON Web Token) — header, payload and signature. Auto-detect exp, iat, nbf claims with human-readable timestamps and expiration verdict.
{
"alg": "HS256",
"typ": "JWT"
}{
"sub": "1234567890",
"name": "Jay Rajput",
"iat": 1516239022,
"exp": 2000000000,
"iss": "jay.dev"
}What powers the JWT Decoder
Decode header, payload and show signature separately
Auto-detect exp, iat, nbf claims
Human-readable timestamps (UTC + relative)
Big "Token Valid" / "Token Expired" verdict
Validates base64url and JSON structure separately
Pretty-printed JSON for both header and payload
token never sent to any server
Why the JWT Decoder is different
Browser-native
The JWT Decoder runs entirely in your browser. Input is processed locally — never uploaded, never logged, never cached anywhere outside your device.
No artificial limits
No daily quotas, no character ceilings, no "upgrade for more" walls. Every feature is the complete feature — the same on the first use as the thousandth.
Production-grade quality
Built to the same engineering bar as paid SaaS tools — accurate algorithms, audited logic, responsive design and accessibility-tested interactions.
Common use contexts
- Debugging API auth — inspect the token your client is sending
- Verifying the JWT your server issued contains expected claims
- Checking when an issued token will expire
- Learning JWT structure for interview prep or onboarding
Private and secure
Zero upload
All processing happens in your browser. Input is never transmitted, logged or cached.
Works offline
Once the page loads, the tool runs without an internet connection. No network calls happen during use.
No tracking
No accounts, no cookies for tool state. Only aggregate analytics count visits at the page level.