Occasionally, users entering international phone numbers into your website will enter their phone number incorrectly. This often happens when a phone number requires a leading zero when dialed inside the country of origin, but does not require a leading zero when dialed from a foreign country. TeleSign's telephone number cleansing system, which is included with every PhoneID query, recognizes and corrects any incorrectly-entered phone numbers and returns a cleansed phone number properly formatted for dialing from the US.