Number Verification API
Forget frustrating user experiences like extra steps of one-time passcodes (OTP) and multi-step authenticator applications for customer authentication. Vonage Number Verification API (beta) uses the mobile device’s number as an identity credential, and confirms that the number matches with SIM data for validation, via a direct carrier connection. And it’s all without any active user input for authentication. This behind-the-scenes authentication offers a superior customer experience that is more secure, faster and hassle free for end users.
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Enhanced Security
Vonage Number Verification API uses advanced verification technology, reducing the risk of interception or phishing attacks: the direct carrier connection ensures that the number validation is secure and tamper-proof, as the authentication does not depend on potentially vulnerable elements such as OTPs or user recall.Improved User Experience
With legacy authentication methods, users need to manage multiple federated logins and understand how their data is being shared, often resulting in drop-offs and churn. With Vonage Number Verification API, the authentication process happens automatically in the background, with no action needed from the end user. And, there’s no need to wait for and manually enter passcodes, so it’s frictionless and faster.Increased Operational Savings
Improved user experiences drive higher conversion rates and reduced customer abandonment. When customers are happier, businesses see tangible benefits like lower churn rates, ultimately resulting in operational savings. Plus, more secure solutions are crucial to help businesses avoid financial losses from identity and authentication fraud.Greater Reliability
The direct carrier connection ensures a higher success rate for authentication. Why? It doesn’t rely on the delivery of OTPs, which can sometimes fail due to network issues, spam filters or manual misentries.Â
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How Number Verification API works in the real world
From online banking to rideshares, there’s a myriad of ways that Number Verification API can be used to create safer, better experiences.
Self-service banking:Â Ideal, safe and fast secondary authentication step for two-factor authentication (2FA) / multi-factor authentication (MFA).
Verification for account changes: Simplify the verification of customer updates, such as password changes, password resets or contact information.
Payments and transactions: Authorise sales and collect payments securely and enable quick guest checkouts.
Secure file access:Â Ensure that only authorised personnel can access sensitive documents and data.

Simplified access to Number Verification API via the Vonage Network Registry.
The Vonage Network Registry reduces network complexities for businesses and developers and offers a single process and centralised location to register for access to Network APIs. Developers spend less time on administrative tasks and more time on building better and secure applications.
Vonage APIs for Security
Verify, Number Verification, SIM Swap (Beta): Which APIs are right for you? Vonage solutions help make your mobile apps more secure, with less disruption to your customers.
APIs
Best for...
Businesses looking for a single API that offers multi-channel 2FA solutions with built-in redundancy
Number Verification
Secure, seamless and behind the scenes
Frictionless authentication for your mobile apps that checks when a SIM swap was performed on a mobile number
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What goes well with Number Verification? Our SIM Swap API
The SIM Swap API allows developers to determine whether the SIM card linked to the phone number has recently changed. This gives developers the assurance that the phone number can be used for multiple use cases, such as 2FA or as a secure communications channel.

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