Question 1

What algorithm is used?

Accepted Answer

HS256 (HMAC with SHA-256), which is the most common JWT signing algorithm.

Question 2

Can I set custom claims?

Accepted Answer

Yes. Add any custom key-value pairs to the payload in addition to standard claims like exp, iss, sub.

Question 3

Is my secret sent to a server?

Accepted Answer

No. JWT signing happens entirely in your browser using the Web Crypto API. Your secret never leaves your device.

Question 4

Can I set an expiration time?

Accepted Answer

Yes. Choose from preset durations (1 hour, 1 day, 7 days, 30 days) or set a custom expiration timestamp.

Question 5

Is this suitable for production use?

Accepted Answer

This tool is designed for development and testing. For production, use your backend to generate tokens with proper key management.

JWT Generator

Frequently Asked Questions