Cognomen Керсти (Kersti 
, Керсти 
) , around the globe, is a very rare surname. The last name Керсти is characteristic of Spain, where it is a very rare surname, Canada, where it is an extremely rare surname, and Peru. Not in comparison with a country's population, it is the most numerous in China, Spain, and the United States. Much more prevalently, Керсти is the forename as well as the last name.