1
What +1 actually covers
The North American Numbering Plan uses country code 1 for the United States, Canada and several Caribbean territories. The area code after +1 is the next useful signal, not the country code itself.
2
How to look up a +1 number
Paste the 10-digit national number or the full +1 number, then pick United States or Canada on the matching country page. Do not add a second country code.
3
Common mistakes
People sometimes keep a leading 1 twice, drop an area code, or assume every +1 missed call is from the United States. Select the country you care about when the result will be used for a callback.