JWT Exp Decoder

Paste a JWT to decode header and payload locally. Exp countdown and copy — nothing leaves your browser.

JWT Exp Decoder is a minimal, privacy-first JWT inspector for developers who copy tokens from logs, API clients, or DevTools — and want to decode them without pasting into a third-party website. Features: • Paste any JWT — header and payload decoded instantly as formatted JSON • Exp countdown — see time until expiry (or how long ago it expired) with live updates • Copy header, payload, or the full token with one click • 100% local — no network requests, no storage, no telemetry • Zero host permissions — paste-only workflow • English and Chinese UI (follows Chrome language) • Light and dark mode Use cases: debugging OAuth/OIDC flows, checking exp/iat claims, inspecting API tokens, and verifying JWT structure during development. Privacy: No data is collected, stored, or transmitted. Your tokens never leave this browser.