Top 20 NuGet 2factor Packages

.Net library for two-factor (or multi-factor) authentication using TOTP and QR-codes.
Yoti .NET SDK, providing Yoti API support for Login, Verify (2FA) and Age Verification
An ASP.NET Core library for generating and validating one time passwords for google authenticator.
Another Implementation of the Twilio's Authy 2FA Api for .Net Framework
An ASP.NET Core library for generating and validating one time passwords for google authenticator. It seems that dotnet pack has a problem to pack own project. This Package needs AspNetCore.Totp. This is a workaround to not merge my project into one. If you find way of doing it correctly, let me kno...
Sending worldwide SMS messages with the ASPSMS.com API to over 800 mobile networks. This .NET assembly contains all you need to process text messages, two-factor token authentication and other SMS. Get a free test account and free test credits for your project.
Yoti Owin .NET SDK, providing Yoti API support for Login, Verify (2FA) and Age Verification
Latch is a service that lets you add an extra level of security to your online services to help prevent any unauthorized use, Latch gives you the control to switch off your accounts with a single tap when you’re not using them. Security and Control with a single tap.
Latch is a service that lets you add an extra level of security to your online services to help prevent any unauthorized use.
HMAC-Based One-Time Password Algorithm Implementation for dotnet core. Designed to support two factor authentication with common authenticator apps like the Microsoft and Google authenticators.
FIDO Universal 2nd Factor (U2F) library for .NET. Please have a look at the project page for examples.