Verify API

Validating genuine customers just got easier. 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
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Get secure 2-factor authentication (2FA) globally with Verify. Prevent fraud and reach users with PIN code or OTP on SMS and Voice channels with full-service Verification API.


Give your customers the ability to generate and manage their own PIN codes.


Empower your clients to tailor the failover sequence to other channels.


Authenticate end users using your preferred channel across countries in line with local compliance, and add channels as they become available.

Only pay for success

Put your customer success at the forefront and only pay for conversions.

See how Verify helps businesses like yours succeed.

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Acquire genuine customers

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

  • A single API offers a full two-factor authentication solution
  • Provide a phone number and we’ll generate codes, localize, and more
  • Works with any phone number—no additional hardware or apps required
  • Pay only for successful conversions or a flat monthly fee for frequent logins
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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

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
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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

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™

Optimize delivery by proactively re-routing messages around congestion.

Flexible implementation

Choose from three Verify models: Verify Success, Verify Request or Verify Conversion.

Learn how others verify their conversations with Vonage APIs.

Try it free

Start developing now with free credit. No credit card required.
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Speak with an expert.

US toll-free number: 1-844-365-9460
UK toll-free number: +44 800 086 9444