Cognomen Радка (Radka 
, Радка 
) , in all the world, is quite a common surname. The last name Радка is characteristic of Bulgaria, where it is a common surname, Czechia, where it is quite a rare surname, and North Macedonia. Measured by absolute frequency, this name is the most popular in Bulgaria, Czechia, and the United States. More prevalently, Радка is the forename as well as the last name.