Polk global market registration data revealed sales of the Focus totalled 1,020,410 cars worldwide in 2012 to take the title of world's best-selling vehicle overall.
It also confirmed the Ford Fiesta as the best-selling subcompact car globally, with 723,130 registrations last year.
"Focus and Fiesta represent the culmination of our One Ford global product strategy," said Jim Farley, Ford Executive Vice President, Global Marketing.
"Our global products are resonating with consumers – especially in the best-selling, most competitive segments – with their unique combination of fuel efficiency, high quality, rich content and fun-to-drive personalities.
"Through One Ford, we're able to bring economies of scale and fantastic value to customers all around the world."
The Focus in Europe last year became the first Ford to be offered with the innovative 1.0-litre EcoBoost petrol engine that went on to be named the International Engine of the Year 2012.