Authenticator app

An authenticator app is an app on your phone that generates short-lived codes you type in after your password as a second step.

What it means for you

It is usually a stronger choice than text-message codes and works without a phone signal. Save your recovery codes somewhere safe, because a lost phone can lock you out; our 2FA guide covers free options.

Guides on this topic

• 2FA, Passkeys and Security Keys for Your Home

  Turn on two-factor sign-in with a free authenticator app, add passkeys where offered, and decide whether a security key is worth it.

• Password Managers for a Household: Free Options First

  Start with the free built-in managers from Apple and Google, then compare free Bitwarden and Proton Pass plans, plus breach alerts and a weekend plan.

• How to Secure Your Security Camera

  Seven steps from two-factor sign-in and updates to IoT networks and safe sharing.

Related terms

• Two-factor authentication
• Passkey
• Security key
• Password manager

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Definitions are short and general. For model-specific details, check your device maker’s own documentation.