How country calling codes work
A country calling code is the numeric prefix used before a national phone number when dialing internationally. The code appears after the plus sign, such as +1 for the North American Numbering Plan, +44 for the United Kingdom, +91 for India, +880 for Bangladesh, and +971 for the United Arab Emirates.
Shared country codes need extra care
Some codes are shared by multiple places. The best-known example is +1, which covers both the United States and Canada plus several Caribbean locations. For shared codes, a lookup tool should use the selected ISO country when possible instead of assuming the first matching country.
Country code vs local prefix
The country code is not the same as a local operator prefix. A mobile number may start with a local carrier prefix inside the country, but the international format begins with the country calling code followed by the subscriber digits.