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Two-Factor Authentication Methods

Support Every User

Users can authenticate even when they’re offline, with mobile apps, or just landlines. Users can also have multiple devices, and choose their preferred method during login.

Duo Mobile

One-Tap Authentication.

With our free mobile app for your smartphone, you can authenticate via push notifications. Just one tap lets you approve a request.

Learn More About Duo Mobile Authentication
SMS Passcodes

No Internet? No Problem.

Receive passcodes on your phone by text message, and authenticate by typing them into your secondary login prompt.

Learn More About Duo SMS Authentication
Phone Callback

No Texts Either? No Problem.

Duo will call your cell phone, landline or car phone. All you need to do is answer and press a key to quickly authenticate.

Learn More Phone Callback Security

Duo Push

Quick and Easy Approval

Duo Push lets you approve login requests via your smartphone and smartwatch using the Duo Mobile app. Just tap “Approve” and you’re in.

As out-of-band authentication, Duo Push is resilient against credential-stealing attacks, including bypasses of one-time passwords. Learn more about Duo Push

Hardware Tokens:

Old School, but Effective

We support all OATH HOTP-compatible tokens. We also support YubiKeys!

Learn More About Authentication Tokens

Duo’s Ease of Use, Anywhere.

Some online services and web applications let you protect your account with a mobile generated passcode, with the use of any authentication app.

Learn More About Third Party Authentication
Bypass Codes

Good in a Pinch

Single, event or time-based codes for temporary flexibility and contractors.

Learn More About Bypass Codes

What our customers say

  • “The thing that I personally love about Duo is, the interface is absolutely slick. You just can’t beat the fact that it’s one touch, one button, one press.”

    — Paul Pieralde, Principal Product Security Engineer
     Read the case study
  • “More people are aware of security, since they are now forced to use their phone to log in to some applications. Besides this, we as an IT department feel more secure, because even if hackers get the username/password of our user, they still can’t access without a phone.”

    — Michiel van Leuveren, Solution Developer
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