Country calling codes
Every international dialling code and the countries on it. A code is not a country: 250 countries share 209 codes, and +1 alone covers 25 of them.
reads /api/v1/geo/dialcodes.json
Data by Countries States Cities Database, under ODbL v1.0. Codes are the country prefix only — they do not include area or mobile prefixes, and a few territories share a code with the country that administers them.