How many people did Adolf Hitler kill?

Adolf Hitler did not directly kill anyone, with his own hands (aside from himself and wife Eva Braun in a mutually-assisted suicide/murder on April 30, 1945). However by authorizing the mass extermination of millions, he became responsible for their deaths. This includes 6 million Jews, who were specifically targeted by Hitler because of his racial hatred, as well as, 5 million other minorities such as Communists, homosexuals, the disabled, and Romani. As for the matter of such killing not being direct, a gangster who orders murders but leaves the dirty work to others is every bit as responsible as the direct killers.

Of course, the millions of soldiers who lost their lives fighting for and against Nazi Germany in World War II are on his head. Adding the casualties from World War II would raise this number considerably, to more than 35 million in the European front alone, and as many as 12 million Germans. 70 million people died in the Second World War as a whole.
None. No person actually died by Hitler's hand. This does not alleviate his responsibility for the actions of the Nazis before & during WWII, unless you count his suisicide. For some time, there were rumors that he had murdered his niece , Geli Raubal. However, at the time of her death, Hitler was at a political rally in Nuremberg.
None personally but his regime killed 6,000,000 Jews and 5,000,000 others including: communists, homosexuals, dissidents, artists, poets, Romanies and anyone else.