According to Wikipedia , Celsius is used by all countries except the United States, the Bahamas, Belize, the Cayman Islands and Liberia.” According to the CIA ,“At this time, only three countries – Burma, Liberia, and the US – have not adopted the International System of Units (SI, or metric system) as their official system of weights and measures.” So, the overlap would be the USA, and Liberia. The countries using Fahrenheit and Metric would be the Bahamas, Belize, and the Cayman Islands. And the one country using Celsius and not using Metric would be Burma. Perhaps related, the CIA is still calling Burma “Burma” rather than Myanmar.