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International Telephone Input Validation

Created by: Twilio
  • Verify
  • JavaScript
  • Quick Deploy

This template provides a production-ready international phone number input form with automatic formatting, country detection, and validation using the Twilio Lookup API v2.

International phone number input with validation

Key Features

  • Automatic formatting using the intl-tel-input library (v23.1.0)
  • Country detection based on user's geographic location
  • Client-side validation with real-time format checking
  • Server-side verification via Twilio Lookup API v2
  • E.164 format conversion for global compatibility

Production Best Practices

For production phone number collection, we strongly recommend adding phone verification(link takes you to an external page) to confirm users have control of the number.

Related Resources

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