Live time-based one-time password codes from your Base32 secret (RFC 6238). Matches Google Authenticator, Authy and similar apps — fully offline.
TOTP combines the shared secret with a counter derived from the Unix timestamp: counter = floor(unix_time / period). The counter is HMAC-signed, and a dynamic-truncation step extracts a 31-bit number that is reduced modulo 10digits. Because both sides know the secret and the clock, the codes stay in sync — typically within a 30-second window with the current and previous periods accepted for drift tolerance.