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
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See how Verify helps businesses like yours succeed.

Preempt Fraud

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


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


Authenticate end users using your preferred channel across 225+ countries in line with local compliance and add channels as they become available.

Pay only for success

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

Try it free

Start developing now with free credit. No credit card required.
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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
  • Provide a phone number and we’ll generate codes, localise and more
  • Works with any phone number — no additional hardware or apps required
  • Ensure PIN codes are delivered over SMS and TTS 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
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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
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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

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

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

See how businesses like yours are using Vonage APIs today.

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Secure valuable video conversations with Verify API
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