Surname Койдер (Kojder 
, Койдер 
) , throughout the world, is a rare last name. The family name Койдер is habitual in Poland, where it is quite a rare surname, Bahrain, and Denmark, where it is a rare surname. In absolute terms, it is commonest in Poland, the United States, and France. More prevalently, Койдер is the forename as well as the last name.