Guide to Two-Factor Authentication · Duo Security (2024)

Table of Contents

How It Works Why Do I Need This? Supported Devices How Do I Set It Up? Common Issues Would you like to know more? Visit duo.com to learn about Duo's Trusted Access and multi-factor authentication (MFA) solutions for every organization.

This guide is intended for end-users whose organizations have already deployed Duo. If your organization isn't using Duo and you want to protect your personal accounts, see our Third-Party Accounts instructions.

Two-factor authentication adds a second layer of security to your online accounts. Verifying your identity using a second factor (like your phone or other mobile device) prevents anyone but you from logging in, even if they know your password.

How It Works

Enter username and password as usual
Use your registered device to verify your identity
Securely logged in

Once you've enrolled in Duo you're ready to go: You'll login as usual with your username and password, and then use your device to verify that it's you. Your administrator can set up the system to do this via SMS, voice call, one-time passcode, the Duo Mobile smartphone app, and so on.

No mobile phone? You can also use a landline or tablet, or ask your administrator for a hardware token. Duo lets you link multiple devices to your account, so you can use your mobile phone and a landline, a landline and a hardware token, two different mobile devices, etc.

Why Do I Need This?

Passwords are increasingly easy to compromise. They can often be stolen, guessed, or hacked — you might not even know someone is accessing your account.

Two-factor authentication adds a second layer of security, keeping your account secure even if your password is compromised. With Duo Push, you'll be alerted right away (on your phone) if someone is trying to log in as you.