Phone number validator and formatter

What “valid” means here

A valid number is one whose length and prefix exist in the country’s numbering plan, the ranges regulators assign to carriers. It does not tell you whether the line is switched on or who owns it: the check runs in your browser on the open numbering data of Google’s libphonenumber, and the number is not looked up in any carrier or owner database.

To show a price for a valid number, we ask our own price list for its rate, as the dialer does; the number is not saved.

E.164, international and national formats

E.164 is the compact international form: a “+” followed by the country code and the number, with no spaces (+442079460000). It is what apps, CRMs and messaging services expect. The international format adds spaces for reading (+44 20 7946 0000). The national format is how people dial inside the country, often with a leading 0 (020 7946 0000) that you drop when calling from abroad.

Mobile or landline?

Many countries give mobiles and landlines different prefixes, so the numbering plan tells them apart. In the United States and Canada they share the same area codes, so a number there can only be identified as “landline or mobile”. A number ported to another carrier keeps its original prefix, so treat the type as a strong hint, not a guarantee.