How to use your phone as a two-factor authentication security key

If you want to verify your Google login and make it harder to access by anyone but yourself (always a good idea), one way is to use your iPhone or Android smartphone as a physical security key. While you can set up a third-party 2FA app such as Authy or even use Google’s own Authenticator, these require that you enter both your password and a code generated by the app. Google’s built-in security allows you to access your account by just hitting “Yes” or pressing your volume button after a pop-up appears on your phone. You can also use your phone as a secondary security key.

Use your phone to sign in

To set this up, your computer should be running a current version of Windows 10, iOS, macOS, or Chrome OS. Before you start, make sure that your phone is running Android 7 or later and that it has Bluetooth turned on.

• While it’s unlikely you have an Android phone that doesn’t have a Google account associated with it, if you’re one of the few, you need to add a Google account to your phone by heading into Settings > Passwords & accounts, scroll down to and select Add account > Google
• Once that’s done, open a Google Chrome browser on your computer
• Head into myaccount.google.com/security on Chrome and click on Use your phone to sign in

• Enter your account password. You’ll be asked to satisfy three steps: choose a phone (if you have more than one), make sure you have either Touch ID (for an iPhone) or a screen lock (for an Android), and add a recovery phone number.

You’ll then be run through a test of the system and invited to turn it on permanently.

Use your phone as a secondary security key

You can also use your phone as a secondary security key to ensure that it is indeed you who are signing into your account. In other words, to get into the account, it will be necessary to be carrying the correct phone with a Bluetooth connection.

• If you don’t have two-step verification set up yet, go back to your account security page, click on 2-Step Verification and follow the instructions. The TL;DR is that you’ll need to log in, enter a phone number, and select what secondary methods of verification you’d like.
• Scroll down the list of secondary methods and select Add security key.
• And again, select Add security key.

• You’ll be given the choice of adding your phone (or one of your phones, if you have more than one) or a physical USB or NFC key. Select your phone.
• You’ll get a warning that you need to keep Bluetooth on and that you can only sign in using a supported browser (Google Chrome or Microsoft Edge).

That’s it! You’ve set up your phone as a security key and can now log in to Gmail, Google Cloud, and other Google services and use your phone as the primary or secondary method of verification.

Just make sure your phone is in close proximity to your computer whenever you’re trying to log in. Your computer will then tell you that your phone is displaying a prompt. Follow the directions to verify your login, and you’re all set!

Update March 29th, 2021, 11:20AM ET: This article was originally published on April 12th, 2019, and has been updated to account for changes in the Google interface.