Secure JWT Decoder
in your browser
Parsy transforms raw API responses, config files, and tokens into beautiful, interactive views — instantly. No copy-pasting, no external tools.
From encoded token to readable claims
Never paste an active access token into a third-party website again.
exp / iat / nbf timestamps to readable dates with a valid/expired badgeBuilt for auth debugging
aud, iss, sub, scope claimsAuthorization: Bearer tokens from network requestsA JWT decoder built for developers
Every feature is crafted for speed and productivity. No bloat, no tracking.
Header & Payload Decoder
Splits any JWT into Header and Payload and renders both as readable, collapsible JSON.
Expiry & Validity Badge
Automatically compares exp to the current time and shows a clear valid/expired indicator.
Dark & Light Themes
Premium glassmorphism design in both modes. Switch instantly from the toolbar or popup panel.
Search Claims
Press Ctrl+F to jump between claims in large tokens.
Paste or Drop Safely
Decode a token pasted into the File Viewer — fully offline, nothing transmitted.
Zero Dependencies
100% pure JavaScript. No external libraries, no network requests, no tracking.
Premium developer experience
Every pixel is designed to reduce friction and enhance readability.
Stop squinting at raw data
Install Parsy in one click. Free forever, no account needed.
Install on Chrome — It's FreeThe safest way to decode a JWT
JSON Web Tokens (JWT) are everywhere in modern web authentication, but decoding them usually means copying and pasting a live access token into a third-party website. Parsy avoids that risk entirely with a local JWT decoder that runs directly in your browser.
Navigate to a page containing a raw JWT, or paste one into the File Viewer, and Parsy instantly splits it into Header and Payload. It converts Unix timestamps into human-readable dates and visually flags whether the token is still valid or has expired.
Frequently asked questions
Does Parsy verify the JWT signature?
No. Parsy decodes the Header and Payload for inspection — it does not cryptographically verify the signature, which would require the signing secret or public key. It's a read-only debugging tool, not a security validator.
Is my token ever sent to a server?
No. Decoding happens 100% locally in your browser using pure JavaScript. Nothing is uploaded, which matters for live access tokens.
What's the difference between Parsy and jwt.io?
jwt.io requires pasting your token into a website, which some teams avoid for sensitive tokens. Parsy decodes entirely offline in your own browser tab, with no network request involved.
Which JWT signing algorithms are supported?
Parsy decodes the Header and Payload of any JWT regardless of signing algorithm (HS256, RS256, ES256, etc.), since reading the claims doesn't require the signing key — only verification does.
Can I check if a token is expired?
Yes. Parsy compares the exp claim to the current time and shows a clear valid or expired badge next to the decoded payload.
More Parsy tools
JSON Viewer · XML Formatter · CSV Viewer · YAML Viewer · Markdown Preview