Validate and Format Phone Number API

What it does

The phone validation API checks whether a phone number is valid for its country and returns it in formats you can store and compare. Send phone in E.164 form (with the +) or in national format with an ISO alpha-2 country hint such as GB or BR. You get back valid, the normalized e164 value, national_format, international_format, national_number, calling_code, country_code and the resolved country.

Use this phone number validation API at signup and checkout to catch mistyped numbers before an SMS code or delivery update goes nowhere. The country hint lets users type numbers the way they write them locally, such as 020 7946 0958, while your database keeps one consistent e164 value.

Normalizing to E.164 also makes contact data easier to work with. Deduplicate CRM records where the same person was saved as +44 20 7946 0958 and 020 7946 0958, match inbound calls to customer accounts, and clean phone columns before an import or migration.

Validation here follows each country's numbering rules. It does not contact the carrier or confirm the line is active, so a valid result means a correctly structured number for that country.

For carrier name, line type and time zone, use the Phone Carrier Lookup API. Signup forms usually collect more than a phone number, so pair it with the Email Validation API and the Address Validation API.