--- title: Two Factor Authentication [Use Cases] canonical: https://telnyx.com/use-cases/two-factor-authentication --- # Two Factor Authentication \[Use Cases\] **Use Case** # Two-factor authentication **About** ## Build your own two-factor authentication solution Businesses use two-factor authentication (2FA) to block over 99% of automated account attacks on average. But historically, building your own 2FA has been laborious, and out-of-the-box solutions have limitations of their own. Telnyx offers SMS, Voice and Verify APIs that enable developers to quickly and easily incorporate accessible 2FA at any point in the customer journey. ## Benefits ## Build a native experience Send passcodes via SMS, voice call, flash call or WhatsApp message. 4 ## Authentication channels ## Integrate 2FA easily Secure logins, authenticate devices, confirm account changes, register users, protect payments and stay PSD2 compliant with Telnyx’s Verify API. 1 ## flexible API **How It Works** 1. **1** ### Set up verification-capable phone numbers Instantly provision and configure [phone numbers](#) for calling and messaging in 200+ countries via the Telnyx Mission Control Portal. 2. **2** ### Configure your application to interact with the Telnyx Verify API Set up your application to call the Telnyx Verify API when the user submits the correct criteria. This will trigger a PIN code to be sent via SMS, voice, flash call or WhatsApp to the phone number associated with that user’s account. 3. **3** ### Deliver and verify PIN codes The user receives a code and enters it into your application’s PIN code input field. Your application then sends a request to the Verify API with the user’s details and entered PIN code to check if it’s correct. 4. **4** ### Verify API responds with appropriate result If the code matches the one generated, the API will send a positive response, and your application can grant the user access in accordance with your configuration. If it isn’t, the API will deliver a negative response, and you can ask the user to try again or request a new code. Products ## Flexible APIs over a private IP network [See all products](https://telnyx.com/products) * [![Verify API-Typing on cellphone image](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/Product_Thumbnail_Comms_Verify-API-8b3add95.png?width=640&format=webp)Verify APIAuthenticate accounts via SMS, voice call, flash call or WhatsApp message at any point in your user journey.Learn More](https://telnyx.com/products/verify-api) * [![Woman sends text message](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/Product_Thumbnail_Comms_SMS-API-0905ed67.png?width=640&format=webp)SMS APIProgramatically send and receive SMS alerts, notifications, marketing messages and more in 200+ countries.Learn More](https://telnyx.com/products/sms-api) * [![Telnyx Cloud Storage Product Animation](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/Product_Thumbnail_Storage_Storage-bdc04c52.png?width=640&format=webp)Voice APIKeep your VoIP off the public internet. Host secure, high-quality calls with granular customization and control.Learn More](https://telnyx.com/products/voice-api) **Resources** * ### Build with an authentication API Configuration guides to quickly add an authentication service to your app using SMS, Voice, Flash Call and/or WhatsApp. [Explore docs](https://developers.telnyx.com/docs/identity/verify/quickstart) * ### How secure is two-factor authentication? If you're worried about protecting your sensitive and personal information, learn how two-factor authentication can help. [Read article](https://telnyx.com/resources/is-two-factor-authentication-secure) * ### What is two-factor authentication? We dive into how two-factor authentication works to add an extra layer of security, the different types of 2FA and more. [Read article](https://telnyx.com/resources/what-is-two-factor-authentication) ## Ready to get started? [Sign up](https://telnyx.com/sign-up)[Contact us](https://telnyx.com/contact-us) ## FAQ ### What is two-factor authentication? Authentication is a means of verifying one’s identity, and two-factor authentication (2fa) is a method of establishing access to an online destination, by requiring users to provide two different types of information. One common mode of single factor authentication is the username password pair. With 2FA, users need to both provide a password and prove your identity some other way to gain access. A common 2FA method is to send a time expiring one time password, sent to a mobile device via SMS in addition to username and password. ### How do I set up two-factor authentication? ### Is MFA secure? Is 2FA secure? How secure is it? ### What is Verify API? ### Which two-factor authentication is best? ### What is flash calling? [Start building](https://telnyx.com/sign-up) ### Ask AI * [![GPT](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/chatgpt_icon-ea55e09d.jpeg?width=92&format=webp)](https://chat.openai.com/?q=What makes Telnyx's global network different, breakdown call quality for normal phone calls and voice AI calls.) * [![Claude](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/claude_icon-c7c8eef3.webp?width=92&format=webp)](https://claude.ai/new?q=What makes Telnyx's global network different, breakdown call quality for normal phone calls and voice AI calls.) * [![Perplexity](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/perplexity_icon-cd5b74f1.webp?width=92&format=webp)](https://www.perplexity.ai/search?q=What makes Telnyx's global network different, breakdown call quality for normal phone calls and voice AI calls.) * [![Gemini](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/gemini_icon-4ff1cbf4.webp?width=92&format=webp)](https://www.google.com/search?udm=50&aep=11&q=What makes Telnyx's global network different, breakdown call quality for normal phone calls and voice AI calls.) * [![Grok](https://d2efw2akbx8gaf.cloudfront.net/https://dotcom-payload-assets-prod.s3.us-east-1.amazonaws.com/cms-media/grok_icon-e588e5bd.webp?width=92&format=webp)](https://x.com/i/grok?text=What makes Telnyx's global network different, breakdown call quality for normal phone calls and voice AI calls.)