Coolen (Dutch pronunciation: [ˈkoːlə(n)]) is a Dutch patronymic surname.
[1] Variant forms are Colen, Kolen and Koolen.
Cool and Kool are archaic short forms of the given name Nicolaas.
[2][3] In Canada the name may also have evolved as a modern spelling of Coulon.
[4] Notable people with this surname include: