If you lose your phones or otherwise can't receive codes via SMS, voice call, or Google Authenticator, you can use backup codes to sign in. These codes are available on your Accounts overview page and were first offered to you at the end of the 2-step verification setup.
The codes come in sets of 10, and you can generate a new set at any point, automatically making the old set inactive. In addition, after you’ve used a backup code to sign in, it will become inactive.
We recommend you store your codes wherever you keep your other valuable items. Like the codes on your phone, backup codes are only valuable to someone if they manage to also steal your password.
If you are fine using the current set of backup codes, you can print or download them. If you believe this set of codes might have been stolen or you’ve used many of the backup codes, you can generate a new set by clicking Generate new codes.
Can't find the backup codes you downloaded? Search your computer for "Backup-codes-username.txt" with your username. If your username is google123, search for "Backup-codes-google123.txt".
Signing in
Locate your backup codes.
Go to the sign-in page of the Google service you want to use (for example, Gmail).
Enter your username and password.
Enter your backup code in the box next to the phone icon, where you would normally enter your verification code.
Optional: As each code can be used only once, you might want to mark the code as used.
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Verified answer
Basics of backup codes
If you lose your phones or otherwise can't receive codes via SMS, voice call, or Google Authenticator, you can use backup codes to sign in. These codes are available on your Accounts overview page and were first offered to you at the end of the 2-step verification setup.
The codes come in sets of 10, and you can generate a new set at any point, automatically making the old set inactive. In addition, after you’ve used a backup code to sign in, it will become inactive.
We recommend you store your codes wherever you keep your other valuable items. Like the codes on your phone, backup codes are only valuable to someone if they manage to also steal your password.
Creating and viewing a set of backup codes
To create a new set of backup codes:
Sign in to your accounts at https://www.google.com/accounts/SmsAuthConfig.
Look for the “Printable backup codes” area.
Click Show/Generate codes.
If you are fine using the current set of backup codes, you can print or download them. If you believe this set of codes might have been stolen or you’ve used many of the backup codes, you can generate a new set by clicking Generate new codes.
Can't find the backup codes you downloaded? Search your computer for "Backup-codes-username.txt" with your username. If your username is google123, search for "Backup-codes-google123.txt".
Signing in
Locate your backup codes.
Go to the sign-in page of the Google service you want to use (for example, Gmail).
Enter your username and password.
Enter your backup code in the box next to the phone icon, where you would normally enter your verification code.
Optional: As each code can be used only once, you might want to mark the code as used.
Please go here, it will show you how through pictures. https://support.google.com/accounts/answer/1187538...
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