Kabul police chief Gen. Mohammad Zahir Zahir said Saturday that the victims included 13 foreigners and eight Afghans, and that the majority are civilians.
He says the three attackers, including a suicide bomber and two gunmen, were also killed during Friday's assault on the Lebanese restaurant.
The American University of Afghanistan says that two of its U.S. employees were killed.
The dead also included the head of the International Monetary Fund in Afghanistan and three United Nations staff members.
The Taliban claimed responsibility for the attack.
Insurgents have frequently targeted foreign interests around the country and in Kabul.