JWT Decoder & Token Inspector

Decode any JWT instantly — header, payload, and claims shown as readable JSON. Fully offline, zero data leaves your device.

Decode any JSON Web Token in a tap and read the header, payload and signature as clean, pretty-printed JSON — right on your device, with nothing sent to a server.

Built for developers debugging authentication flows, this app turns an opaque bearer string into something you can actually read: colour-coded segments, every claim laid out, and a live expiry countdown so you know at a glance whether a token is still valid.

WHY DEVELOPERS USE IT

• Instant decode — header, payload and signature as formatted JSON • Full claim inspection — issuer, subject, audience, exp and iat shown as real dates • Live expiry status so you never chase a stale token • Verify HMAC signatures with HS256, HS384 and HS512 • alg:none warnings plus a built-in security reference • Saved token history, kept on your device only • Fully offline — no server, no logging, no tracking

HOW IT WORKS

1. Paste your JWT, or load the sample token
2. Read the decoded header, payload and each claim
3. Enter your secret to verify the HMAC signature

FULL ACCESS

Signature verification, saved history and the security reference are unlocked with a subscription, offered weekly or yearly, or as a one-time lifetime purchase. Decoding and claim inspection let you try the core workflow first.

Paste a token and see exactly what's inside.

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