Number Insight API

The Vonage Number Insight API (formerly Nexmo) makes the most of existing customer data to secure fresher insights from real-time sources. Now you can identify phone numbers around the world and determine the best way to reach customers. Assess risk, prevent fraud, block fake accounts and increase acquisition — all without relying on customer input.
Try it free
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See how our Number Insight API helps businesses like yours succeed.

Offer an enhanced customer experience

Identify callers and anticipate customer intent with Caller Identification.

Verify customers in context

Authenticate customers based on their intent — from sign up to sign in — with Tiered User Verification.
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Validate

Phone number validation

Validate the legitimacy of customer phone numbers to confirm reachability and reduce delivery errors.

  • Distinguish mobile numbers from landlines
  • Minimise fraud while guaranteeing a verified way to contact customer in the future
  • Reduce delivery errors across SMS- or voice-based marketing campaigns
  • Discover carrier to optimise SMS routing
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Security

Fraud detection and step-up verification

Prevent costly fraudulent transactions using up-to-date phone number intelligence.

  • Detect possible fraud and trigger step-up authentication when needed
  • Reduce customer friction with additional steps only for suspected numbers
  • Leverage Number Insight to deliver real-time phone number intelligence
  • Determine if a phone number is valid, reachable, a virtual number or a landline and more

See how businesses like yours are using Vonage APIs today.

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Try it free

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

UK free phone number: 0330 808 9348