Device Type: desktop
Skip to Main Content Skip to Main Content

Verify API

Validate customers easily across the world at scale. Our patented 2FA technology helps you protect against fraud, build trust and increase conversion across multiple channels — no telecom or security experience required. Plus, you’ll only pay for successful verifications.

Try it free
Verify API thumbnail image
Illustration of a group of happy, excited customers standing in front of a large brain, representing AI.

Verify V2

Our enhanced Verify V2 API is now available.  Start using our new authentication channels now!

Verify V2

Our enhanced Verify V2 API is now available.  Start using our new authentication channels now!

Learn more

See how Verify helps businesses like yours succeed

Prevent Fraud

Use up-to-date intelligence on phone numbers to detect potentially fraudulent transactions. The second step in 2-factor authentication easily minimises fraud with an extra layer of security.

Multiple Authentication Channels

In addition to SMS and Voice (TTS), authentication can be accomplished over WhatsApp, email and Silent Authentication, allowing you to authenticate 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.


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

Only Pay for Successful Authentications

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





Try it free

Start developing now with free credit. No credit card required.
Screen grab of the API Developer Center showing code that can be copied for use.

Authentication Channels

A laptop and mobile device with a verify pin code


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.
Stylized illustration of a mobile phone with pop ups of a SMS message and sound waves


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.
WhatsApp Messages


Leverage WhatsApp to authenticate users in two different ways. By delivering an OTP or by simply pressing "yes" or "no" within WhatsApp to verify identity. No code to memorise! Learn more
Icons of SMS, phone, online, email communications; with customers


Unable to Verify using a phone? Send a one-time passcode to any email address to authenticate. Learn more
Illustration of a hand holding a cell phone. On the phone screen are a row of four asterisks representing a verification code.

Silent Authentication

Streamline verifications to just a few seconds without requiring any user input by using Silent Authentication. Learn more
Illustration of two people walking with mobile devices

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


Protect your business from scammers

Prevent expensive unauthorised 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

Eradicate unsolicited messages more effectively

Block botnets and bulk account creation via frictionless phone verification for mobile users.
  • Suppress spam
  • Minimise personal information sharing
  • Give every user a unique identifier via their phone
  • Confidently grow your application’s audience
Illustration depicting two-factor authentication; a cell phone shows a four digit-code, behind it a computer screen has a row of boxes for the code to be entered

Provide convenience without compromise

Guarantee safe access by delivering time-limited, single-use authorisation 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 access your application successfully

Get smarter fail-safe, reliable delivery, and tailor-made messaging

Global Text-to-Speech (TTS)

TTS in 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™

Optimise delivery by re-routing messages proactively 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 how businesses like yours are using Vonage APIs today

Secure valuable video conversations with Verify API

Contact a Vonage expert.

We'll get back to you shortly.