Answer:
Estimates range from about 50-70 million killed in World War 2. The Wikipedia article "World War II Casualties" favours the relatively high figure of 72 million. Of these, 61 million were on the Allied side and 11 million were on the Axis side. The article gives a figure of 23 million dead for the Soviet Union and 20 million for China. These figures of course include civilian dead. (Note that the figure for China was recently revised sharply upwards from earlier estimates of about 11 million).
For Germany the overall total is given as just under 7.4 million.
When scholarly sources differ on the number of deaths in a country, a range of war losses is given, in order to inform readers that the death toll is uncertain or disputed. One also needs to know whether the statistics, especially for civilian dead, include deaths from war-related famine and disease.
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