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Vonage / Verify

Simplify user identity verification with SMS short codes

Easily send messages via Vonage Messages

Nexmo is now called Vonage, but there are still references to Nexmo in our URLs, code snippets and message templates.

The effective cross-channel two-factor authentication technology of the Vonage Verify API helps you to protect your users and business against fraud and spam. Build trust and increase conversion across channels by sending a short code (PIN) to your user's telephone, verifying user identity. No telecom or security experience is required with this all-in-one, economical user verification API.

How it works

Vonage's Verify API verifies the identity of your user. When a user logs into his account on your app, Verify sends a one-time verification code to the phone number associated with the username and password, via an SMS, voice message or push notification. The user enters the verification code into the input box presented by your app. This confirms that the person attempting to access the account has the phone linked to that account. Your app then gives full access to the user.You only pay for successful verifications.

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GDPR compliance: Yes
SLA: Standard via the KPN Developer Portal


Coverage: Global
Data center location: US & EU
End-to-end encryption: Yes
Scalable infrastructure: Yes

ISO/IEC 27001:2013, 27017:2015 & 27018:2014
ISO 22301:2012 & 31000:2009
SOC 2 & 3 
NIST 800-171

This API helps you to...

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Provide convenience via SMS

Ensure convenient access to your apps by replacing static passwords with safe, time-limited, single-use, SMS short codes.

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Verify user identity with SMS short codes

Easily add a layer of protection by two-factor authenticating new and existing customers with SMS PIN codes.

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Protect from fraud and spam

Detect possible fraud and spam using up-to-date telephone number intelligence and trigger extra authentication when needed.

What our customers say

Product page Vonage Verify API Testimonial Vinted
"One of the reasons we chose Vonage rather than other SMS verification vendors was because the pricing model for Vonage’s Verify API is unique and very, very attractive for us. Vonage’s charges are based on successful verifications only. If we are checking just the suspicious members that are flagged, it means that we’re not spending money on those fraudulent users because their numbers will not be able to be verified. That saves Vinted a lot of money."
Danielius Isiunas
Product Manager - Vinted


Intelligent fail-over

Automatically resends codes to customers with a single API request. No additional code needed.

Adaptive routing

Ensures optimum delivery by proactively re-routing messages around congestion.

Pay per verification

Pay only for successful verifications, regardless of where users are based.


Pay per successful verification. All prices may be subject to change at any time. Countries not in this list are not available for Verify Success.


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