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Duo Mobile

Convenient, 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 

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 

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 

Duo Push

Quick, One-Tap Approval

Duo Push lets you approve login requests via your smartphone with Duo Mobile installed. Just tap Approve and you’re in.

As an out-of-band authentication method, Duo Push is resilient against credential-stealing attacks, including malware bypasses of one-time passwords.

Learn More About Duo Push 

Get Duo Mobile free

One Tap Authentication Methods


Tokens: Old School, but Effective

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


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.

Bypass Codes

Good in a Pinch

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

From online to offline, mobile apps to landlines to tokens.

Users can have multiple devices and choose their method during login.

Duo Push Mobile Authentication Solutions
Duo Push
Duo Mobile Time Based One Time Password Generator
Duo Mobile Passcodes
SMS Passcode Authentication Solution
SMS Passcodes
Phone Callback Authentication
Phone Callback
Hardware Token Authentication
Hardware Tokens
Description Duo sends a login request to your phone. Just tap Approve to authenticate. Generate passcodes with Duo's free mobile application. Receive a batch of passcodes via SMS. Duo calls your phone. Just press any key to authenticate. Use the passcode generated on your hardware token.
Platforms Duo Push platforms, as well as Palm, Windows Mobile, and J2ME/Symbian All phones with SMS All phones YubiKeys and all OATH-compliant tokens
Offline usage?

Store a batch for offline use

Additional cost? Always free for all customers.
We never charge for our mobile applications or authentication methods.
Phone calls and SMS messages use your account's telephony credits.
Most paid accounts include 100 credits/user/mo.
Buy hardware tokens from us, or import your own for free.

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