Number Verification

Verify mobile identity instantly with network-based authentication. No OTP, no user friction.

Overview

The Number Verification API provides real-time verification that a mobile device's phone number (MSISDN) matches a number provided by the customer. It eliminates manual input requirements like SMS OTP codes, simplifying processes such as account creation, login, and transaction validation.

Unlike traditional SMS-based verification, Number Verification uses network-based authentication — the operator identifies which SIM is assigned to the requesting IP address and confirms the match cryptographically. This is faster, more secure, and eliminates the risk of SIM swap fraud during verification.

How It Works

01

User initiates verification

Your app sends a verification request from the user's mobile device. The request must originate from the device's mobile data connection.

02

Network identifies the device

The mobile operator identifies which SIM card is assigned to the requesting IP address using its core network infrastructure.

03

Number is verified

The operator compares the provided phone number against the SIM's registered number and returns a boolean match result — all in real time.

API Endpoints

POST/number-verification/v1/verify

Validates if a provided phone number matches the device's registered number.

// Request
{
  "phoneNumber": "+34629341502"
}

// Response
{
  "devicePhoneNumberVerified": true
}
GET/number-verification/v1/device-phone-number

Retrieves the phone number associated with the user's device.

Use Cases

Seamless Onboarding

Verify phone numbers during account registration without requiring users to enter or confirm OTP codes. Reduces drop-off by up to 30%.

Multi-Factor Authentication

Cryptographically secure possession factor. Stronger than SMS OTP because it cannot be intercepted or redirected via SIM swap.

Transaction Verification

Confirm the user's identity during high-value financial transactions. Real-time verification adds a network-level security layer.

Fraud Prevention

Detect and prevent account takeover by verifying the phone number matches the actual device in real time.

Supported Operators

Number Verification is one of the most widely deployed CAMARA APIs, available across major operators worldwide:

Deutsche TelekomOrangeVodafoneTelefónicaTelstraT-MobileAT&TVerizonBT GroupSwisscom

Available in 21+ markets including Germany, Spain, UK, Netherlands, and more. Learn more at CAMARA Project →

Ready to verify?

Start integrating Number Verification into your application today.