otplibOne-Time Password Library
TypeScript-first library for HOTP and TOTP / Authenticator with multi-runtime and plugin support
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Try It
TOTP
Generates a new token every 30 seconds based on the current time.
Setup
Client (Generate)
Server (Verify)
HOTP
Generates a new token every time the counter is incremented.
Setup
Client (Generate)
Counter: 0
Click to increment the counter and generate the next OTP.
Server (Verify)
Expected Counter: 0
The server accepts any token from the current counter up to a window ahead (resync).