The 1st Marine Division was mauled and remained out of action until the invasion of Okinawa began on 1 April 1945. In total, the 1st Marine Division suffered over 6,500 casualties during its month on Peleliu, over one third of the entire division. The 81st Infantry Division also suffered heavy losses with 3,300 casualties during its tenure on the island.
Postwar statisticians calculated that it took U.S. forces over 1,500 rounds of ammunition to kill each Japanese defender