Paste your Base32 secret and the current 6-digit code appears, refreshing every 30 seconds exactly like an authenticator app.
Time-based One-Time Password (RFC 6238) derives a 6-digit code from a shared secret and the current time, changing every 30 seconds.
Yes — for the same Base32 secret the codes match Google Authenticator, Authy and similar apps.
No — codes are computed locally with HMAC-SHA1 and the secret never leaves your browser.