012 is not a country code. Numbers inside a country start like this: Yerevan (Armenia), Baku (Azerbaijan), Pozarevac (Serbia), Alumínio - SP (Brazil) and others. The first digit 0 is the trunk prefix for domestic calls and is dropped from abroad.
Have the full number? Check it in the number lookup.
| Area or operator | From abroad | Inside the country |
|---|---|---|
 Yerevan · Armenia | +374 12 … | 012 … |
 Baku · Azerbaijan | +994 12 … | 012 … |
 Pozarevac · Serbia | +381 12 … | 012 … |
 Alumínio - SP · Brazil | +55 12 … | 012 … |
| Aparecida - SP · Brazil | +55 12 … | 012 … |
| Arapeí - SP · Brazil | +55 12 … | 012 … |
| 50 more in Brazil | ||
 Tongeren · Belgium | +32 12 … | 012 … |
 Cellcard · Cambodia | +855 12 … | 012 … |
 Kinshasa · Congo - Kinshasa | +243 12 … | 012 … |
 Orange · Egypt | +20 12 … | 012 … |
 Maxis · Malaysia | +60 12 … | 012 … |
 Makkah/Jeddah · Saudi Arabia | +966 12 … | 012 … |
 Brits/Tshwane · South Africa | +27 12 … | 012 … |
| Vodacom · South Africa | +27 12 … | 012 … |
 KT · South Korea | +82 12 … | 012 … |
 Sudatel · Sudan | +249 12 … | 012 … |
 Al-Nebek · Syria | +963 12 … | 012 … |
 MobiFone · Vietnam | +84 12 … | 012 … |
If a number starts with +, the first 1–3 digits are the country code. If it starts with 0 (8 in Russia and Kazakhstan), it is a domestic number: an area or operator code follows, and from abroad the 0 or 8 is replaced with + and the country code. The same digits can mean different places, so where the call came from matters.