Nazism is too easily related to the man who systematically eradicated hundreds of thousands of mostly innocent people. That is my reason for believing it is worse.

The true marxist interpretation of communism is the stateless utopia where wealth and labor are evenly distributed among the masses (I know this as a former Marxist). Nazism is built on the eradication of innocent lives in order to achieve a "racially pure" utopia.

Communism does not mean to murder people, nazism does. Both are bad though.

If we wanted to compare Communist Dictatorships to Nazi dictatorships, I'd vote Communist.

However, the ideology of Communism is not worse than Nazism. Communism specifically goes against government, against property and money, against competition, religion, etc. Nazism is an extreme form of Fascism, purporting ethnic cleansing and executions of anyone deemed unworthy (including political dissidents.) There is no real argument here.

Stalinism and Maoism are, in ways, forms of Fascism and Statism. They purport a Socialist distribution of resources while also creating a ruling class (Democratic or not) and a non-ruling class. The ideologies support authoritarianism while Communism (in the Marxist sense) is against theoretically all hierarchy. As well, there's a major hostility towards so-called Capitalist (wealthy men that work with government in exploiting the lower class).

I could go on and on, but Stalin and Mao's rule were not actually Marxist Communism. They were "state" Communism, dictatorships, etc. Statism is bad in any form.

Communism removes all freedom of thought and kills the ones who disagree with the system, but nazism consists of killing people because they are born in a certain maneer, and lets no choice at all.