OTP / TOTP Generator

TOTP (Time-based One-Time Password) is an algorithm defined in RFC 6238 that generates short-lived numeric codes based on a shared secret key and the current time. It is widely used for two-factor authentication (2FA) in services like Google Authenticator.

Base32 is an encoding scheme that uses 32 characters (A-Z and 2-7) to represent binary data. TOTP secrets are typically shared as Base32-encoded strings because they are easy to type and read, and are the standard format used by authenticator apps.

By default, TOTP codes change every 30 seconds. Some services use a 60-second period. The time step is configurable, and the countdown bar shows how many seconds remain before the next code is generated.

Yes — all OTP generation happens entirely in your browser using the Web Crypto API. Your secret key is never sent to any server. However, you should still treat your secret keys carefully and never share them publicly.

Most services use 6-digit TOTP codes, which provide a 1-in-a-million chance of guessing correctly. 8-digit codes offer greater security with 1-in-100-million odds, and are used by some enterprise applications.