It is calculated using a unique time-based key, provided to you in the 2FA setup stage in iPayroll, and the current time. A 6-digit code (one-time password) is produced using the algorithm. The 6-digit code is regenerated using the new time every 30 seconds.
This 6-digit code is entered into iPayroll after your username and password has been entered, as part of the login process.
In order to generate the 6-digit code, you will need to install a third-party authenticator app.
The app you choose will depend on whether you want the authenticator app installed on your smartphone, tablet, or desktop computer.
iPayroll has put together a list of some of the more common third-party authenticator apps:
You may want to use one of these apps, or research and choose an alternative app for yourself.
Once you have chosen and downloaded your authenticator app, you can either follow the instructions for the specific authenticator app you have downloaded to set up 2FA, if it is one from the list above, or follow the set up instructions in the Quick Set Up Guide for Two-Factor Authentication article.