## Prevent Fraud

2-factor authentication easily minimizes account fraud with an extra layer of security. Fraud Defender protects against traffic pumping fraud with real-time alerting and automatic blocking of suspicious traffic. [Learn more about Fraud Defender](https://www.vonage.com/communications-apis/fraud-defender/)

## Multiple Authentication Channels

Two-factor authentication can be accomplished over SMS, RCS, WhatsApp, Voice (TTS), email and Silent Authentication, allowing you to validate your end-users where they prefer.

## Scale Your Deployments Globally

Whether you have customers in one country or hundreds of countries around the world, Verify takes care of all the heavy lifting so you can focus on your business.

## Customizable

Empower your clients to tailor the failover sequence to other channels, and generate and manage their own PINs.

## Only Pay for Successful Authentications

Efficiency and effectiveness matter. Only pay when your customers successfully verify their accounts.

## Improve CX & Conversions

Boost conversion rates and NPS with Silent Authentication by eliminating friction — no codes, no delays.

#### Own Your Security and safeguard both your business and your customers

[**Protect Your Business** \Defend your brand with next-gen solutions that prevent, detect, and report fraudulent activity.](https://www.vonage.com/communications-apis/protect-your-business/)

[**Protect Your Customers** \Simplify and secure the authentication process … so customers can focus on doing business with you.](https://www.vonage.com/communications-apis/protect-your-customer/)

## SMS

Send one-time passwords (OTP) via the convenience of a text! Deliver SMS using approved sender IDs that are compliant with local rules and regulations.

## RCS

Fully branded, secure and trusted authentication [Learn more](https://www.vonage.com/communications-apis/messages/features/rcs/)

## WhatsApp

Authenticate identity by delivering an OTP to user's WhatsApp account—with Zero-Tap for seamless auto-verification on Android. [Learn more](https://www.vonage.com/communications-apis/messages/features/whatsapp/)

## Voice

Text-to-speech (TTS) adds the personal touch of a human voice to your authentication workflow. Use TTS as a back-up when delivery of SMS is challenged.

## Email

Unable to Verify using a phone? Send a one-time passcode to any email address to authenticate. [Learn more](https://www.vonage.com/communications-apis/verify/features/silent-authentication/)

## Silent Authentication

Eliminate OTPs entirely, making two-factor authentication up to 2x faster and shutting down man-in-the-middle attacks. [Learn more](https://www.vonage.com/communications-apis/verify/features/silent-authentication/)

## Try it free

Start developing now with free credit. No credit card required.

[Start coding](https://ui.idp.vonage.com/sign-up/dashboard?icid=tryitfree_comm-apis-verify_apidevsignup_other&utm_campaign=vonageseo&attribution_campaign=vonageseo)

## Acquire genuine customers anywhere in the world

Easily add a layer of protection by using a phone number to authenticate new and existing customers.

- A single API offers a secure full two-factor authentication solution
- Bring your own number! Or, we can provide numbers for your authentication flow. Works with any phone number—no additional hardware or apps required

- We do the heavy lifting for you, including sender ID management, OTP generation, failover, and fraud monitoring

- Ensure one-time passwords (OTP) are delivered in accordance with country requirements

[See two-factor authentication](https://www.vonage.com/communications-apis/programmable-solutions/2fa/)

## Protect your business from scammers

Prevent expensive unauthorized transactions while delivering a better experience.

- Trigger step-up authentication only for those numbers suspected of being fraudulent
- Use up-to-date phone number intelligence to detect illegitimate transactions

[See Fraud Detection](https://www.vonage.com/communications-apis/programmable-solutions/fraud-detection/)

## Eradicate unsolicited messages more effectively

Block botnets and bulk account creation via frictionless phone verification for mobile users.

- Suppress spam
- Minimize personal information sharing
- Give every user a unique identifier via their phone
- Confidently grow your application’s audience

[See Spam Prevention](https://www.vonage.com/communications-apis/programmable-solutions/spam-prevention/)

## Provide convenience without compromise

Ensure safe access by delivering time-limited, single-use authorization codes with passwordless authentication.

- Let users gain instant and secure access to your app with just their phone
- Works with any type of phone line anywhere in the world—with a single API
- Pay only when users successfully access your application

[See Passwordless Authentication](https://www.vonage.com/communications-apis/programmable-solutions/passwordless-authentication/)

## Global Text-to-Speech (TTS)

TTS in multiple languages to ensure you reach clients all over the world.

## Intelligent failover

Automatically resend PIN codes via voice (TTS) to customers through one API request—without additional code.

## Adaptive Routing™

Optimize delivery by proactively re-routing messages around congestion.

## Flexible implementation

Verify can be tested in minutes and implemented globally in a matter of hours. Choose from two models: Verify Success and Verify Conversion.

[See all features](https://www.vonage.com/communications-apis/verify/features/)

## Network-Powered Mobile Identity

Network APIs enhance Vonage’s mobile identity by integrating real-time, telecom-grade intelligence from mobile operators. Verify’s Silent Authentication eliminates OTPs entirely, making two-factor authentication up to 2x faster and shutting down man-in-the-middle attacks. Unlike traditional methods that rely on SMS-based OTPs, Vonage delivers frictionless, tamper-proof authentication designed to meet modern security standards and rising customer expectations.

[See what’s possible](https://www.vonage.com/network-apis/)