This is the code you need to dial OUT from a country. It is also referred to as the IDD code (International Direct Dialing) or ISD code (International Subscriber Dialing)
This is the code you need to dial IN to a country. Each country is assigned a unique country code.
This is the code for a part of the country. It is usually a general area or a city. Some countries are not large enough to warrant their own code, so will have the country code 1 and use the area code to define the country.
This is the local number you would like to call.
Dialing Code for USA is 1
Here is some useful travel information about USA.
ISO 2 digit Code
ISO 3 digit Code
Area (SQ KM)
This page helps you call from to USA using international country codes.
Area Codes for USA are also supplied. Country Code 1 is for USA.
The dialing code is also described as phone code 1 or dialing code 1 and is sometimes described as a calling code or international dialing code.
The dialing code for USA is 1.