JWT Decoder Online
Decode and inspect JWT tokens. View header, payload, expiry status. Timestamp conversion to human date.
Advertisement
About JWT Decoder & Inspector Online
Decode JWT (JSON Web Token) header and payload without a secret key. View all claims, check expiry status, and convert Unix timestamps to human-readable dates.
JSON Web Tokens are the standard way modern web applications handle authentication — a JWT has three Base64URL-encoded parts (header, payload, and signature) separated by dots, and the payload contains claims like user ID, roles, and an expiry timestamp. A JWT's payload is only encoded, not encrypted, meaning anyone with the token can read its contents without the secret key — the secret is only needed to verify the signature is authentic, not to view the claims. This is a common point of confusion that leads developers to mistakenly put sensitive data in a JWT payload. This tool decodes the header and payload instantly and checks the expiry timestamp, which is useful for debugging auth issues without needing the signing secret.
How to use
- Paste or type your input directly into the editor — output updates in real time as you work.
- Check the error/status indicator if your input is invalid; it points to the exact line or issue where relevant.
- Use the copy or download button to grab the processed output once it looks right.
- Chain into a related tool below if your workflow needs a second processing step.
- Processing happens entirely client-side in your browser — nothing you paste is uploaded to a server.
Tool details
⚡ Next step — complete your workflow
Frequently asked questions
Can I verify JWT signature here?
No. Signature verification requires the secret key. This tool only decodes the header and payload — it does NOT verify authenticity.
Is it safe to paste JWT tokens here?
All decoding happens client-side. However, avoid pasting production JWT tokens containing sensitive user data into any online tool as a security practice.
Advertisement