Google Authenticator

Google Authenticator
Developer(s)Google
Initial releaseSeptember 20, 2010; 14 years ago (2010-09-20)[1]
Stable release(s) [±]
Android7.0 / August 28, 2024; 54 days ago (2024-08-28)[2][3]
iOS4.2.1 / June 26, 2024; 3 months ago (2024-06-26)[4]
Repositorygithub.com/google/google-authenticator
Written in
Operating systemAndroid, iOS, BlackBerry OS, Wear OS
PlatformMobile
LicenseProprietary freeware (some versions were under Apache License 2.0)

Google Authenticator is a software-based authenticator by Google. It implements multi-factor authentication services using the time-based one-time password (TOTP; specified in RFC 6238) and HMAC-based one-time password (HOTP; specified in RFC 4226), for authenticating users of software applications.[5]

When logging into a site supporting Authenticator (including Google services) or using Authenticator-supporting third-party applications such as password managers or file hosting services, Authenticator generates a six- to eight-digit one-time password which users must enter in addition to their usual login details.

Google provides Android,[6] Wear OS,[7] BlackBerry, and iOS[8] versions of Authenticator.

An official open-source fork of the Android app is available on GitHub.[9] However, this fork was archived in Apr 6, 2021 and is now read only.[10]

Current software releases are proprietary freeware.[11]

  1. ^ "Google Is Making Your Account Vastly More Secure With Two-Step Authentication - TechCrunch". TechCrunch. 2010-09-20. Retrieved 2016-03-12.
  2. ^ "Google Authenticator". Google Play. Retrieved 2024-08-30.
  3. ^ "Google Authenticator 7.0". APKMirror. 2024-08-28. Retrieved 2024-08-30.
  4. ^ "Google Authenticator". App Store. Retrieved 2024-08-30.
  5. ^ "GitHub - google/google-authenticator: Open source version of Google Authenticator (except the Android app)". GitHub. 18 May 2022. These implementations support the HMAC-Based One-time Password (HOTP) algorithm specified in RFC 4226 and the Time-based One-time Password (TOTP) algorithm specified in RFC 6238.
  6. ^ "Google Authenticator - Apps on Google Play".
  7. ^ Fingas, Jon (July 19, 2019). "Google Authenticator takes security codes from your smartwatch". Engadget. Archived from the original on October 20, 2020. Retrieved November 6, 2023.
  8. ^ "Google Authenticator". App Store.
  9. ^ "google/google-authenticator-android: Open source fork of the Google Authenticator Android app". GitHub. 16 May 2022.
  10. ^ "google-authenticator/mobile at master · google/google-authenticator". GitHub.
  11. ^ Willis, Nathan (22 January 2014)."FreeOTP multi-factor authentication". LWN.net. Retrieved 10 August 2015.