Here's a summary of the article by Professor Joseph V. O'Brien of the Department of History from John Jay College of Criminal Justice (sorry I don't have the original link):
World War II: Combatants and Casualties (1937 - 45)
Figures are gathered from various sources and, inevitably, are estimates for the most part. The starting point is taken as 1937, when in July of that year China was invaded by Japan in a widening war that continued until the defeat of both Japan and Germany in 1945. The figures for China and the Soviet Union (U.S.S.R.), in particular, may be off by millions. The purpose is to indicate the immensity of the human losses in this most terrible of all wars, one characterized by unspeakable atrocities, germ warfare, enormous civilian casualties, genocide of 5 1/2 million European Jews, and the use of a new and terror-laden weapon of war--the atomic bomb. Estimates of the death toll attributable to the war for military and civilian losses have ranged upward to 60 million, with civilian losses at or more than 50 percent of that total (a stark contrast with the losses of WWI, in which such losses were no more than five percent). The war had a far greater global reach than its predecessor; over 50 countries or dependencies were listed as having some degree of involvement.
The greatest human losses, were suffered by combatants and civilians of the Soviet Union and China. In the near two-and-a-half year siege of Leningrad (now St. Petersburg) by the German forces, 1 1/2 million Russians alone died from shelling, bombing, disease and starvation, a figure that exceeded all the military casualties of the U.S.A.and British Commonwealth combined. The cruelties perpetrated by morally depraved units of the Japanese army in China is demonstrated most vividly in the torture and massacre of civilians and the barbaric killing of war prisoners in the infamous Rape of Nanking that took the lives of over 300,000 Chinese. Other mass civilian deaths, apart from the singular destruction of European Jews, comprise the hundreds of thousands of slave laborers in the Japanese-held Netherlands East Indies (Indonesia) as well as the 1 1/2 million deaths in Bengal as a consequence of war-related famine.
Axis Forces| Country | Pop. | Killed/Mising | Wounded | Total(Military) | Civilian (deaths) |
| Germany | 78m | 3.5 million | 4.6 million | 8.1 million | 2million |
| Italy | 44m | 330,000 | ? | | 70,000 |
| Japan | 72m | 1.75 million | ? | | 350,000 |
| Rumania | 20m | 500,000 | 300,000 | 800,000 | 400,000 |
| Bulgaria | 6m | 10,000 | ? | | 50,000 |
| Hungary | 10m | 120,000 | 250,000 | 370,000 | 200,000 |
| Finland | 4m | 100,000 | 45,000 | 145,000 | 4,000 |
Allied Forces (in order of entry into the war)
| Country | Pop. | Killed/Mising | Wounded | Total(Military) | Civilian (deaths) |
| China | 450m | 1.3 million | 1.8 million | 3.1 million | 9 million |
| Poland | 35m | 130,000 | 200,000 | 330,000 | 2.5million |
| U.K. | 48m | 400,000 | 300,000 | 700,000 | 60,000 |
| France | 42m | 250,000 | 350,000 | 600,000 | 270,000 |
| Australia | 7m | 30,000 | 40,000 | 70,000 | -- |
| India | 360m | 36,000 | 64,000 | 100,000 | -- |
| New Zealand | 2m | 10,000 | 20,000 | 30,000 | -- |
| So. Africa | 10m | 9,000 | 14,000 | 23,000 | -- |
| Canada | 11m | 42,000 | 50,000 | 92,000 | -- |
| Denmark | 4m | 2,000 | ? | ? | 1,000 |
| Norway | 3m | 10,000 | ? | ? | 6,000 |
| Belgium | 8m | 12,000 | 16,000 | 28,000 | 100,000 |
| Holland | 9m | 14,000 | 7,000 | 21,000 | 250,000 |
| Greece | 7m | 90,000 | ? | ? | 400,000 |
| Yugoslavia | 15m | 320,000 | ? | ? | 1.3million |
| U.S.S.R. | 194m | 9 million | 18 million | 27 million | 19 million |
| U.S.A. | 129m | 300,000 | 300,000 | 600,000 | -- |
