If you cannot generate a transfer QR code, or you are switching between app types (e.g., Google Auth to Authy), you need the original secret key.
call or text you asking for this code to "verify your identity" or "fix an account issue". Falkon SMS Are you currently locked out of your account, or are you trying to these portable options for future use? Get verification codes with Google Authenticator - Android 6 digit verification code gmail portable
It requires no battery, no signal, no internet, and no hardware. It works everywhere on Earth. If you cannot generate a transfer QR code,
Do this now, and you’ll never be locked out of your email again—even if you lose your phone on a different continent. Get verification codes with Google Authenticator - Android
No. The 6-digit TOTP changes every 30 seconds. Backup codes (8 digits) are static and single-use. Use backup codes only when you cannot access your authenticator.