King Duncan, Banquo, Lady Macduff, Macduff's son, and two chamberlains are all murdered over the course of the play. There is also the attempted murder of Banquo’s son, Fleance, but it is unsuccessful. Macbeth kills King Duncan himself and hires murderers to dispatch Banquo and to...
King Duncan, Banquo, Lady Macduff, Macduff's son, and two chamberlains are all murdered over the course of the play. There is also the attempted murder of Banquo’s son, Fleance, but it is unsuccessful. Macbeth kills King Duncan himself and hires murderers to dispatch Banquo and to kill the Macduff family. After the discovery of Duncan’s body, Macbeth kills the two chamberlains who slept outside Duncan's chamber. He claims that he killed them in a rage after deducing that they had killed King Duncan, but this was all part of his and Lady Macbeth's plot to pin the blame for Duncan's murder on them. This brings the total count of known murders in the play up to six. Macbeth is responsible for all of them, whether or not he was the one who performed the physical act.
It's implied that Macduff's family is bigger than what the audience sees on stage. The audience witnesses only the murders of Lady Macduff and her son, but when Macduff is told of the murder of his family, his response is, “All my pretty chickens? Did you say ‘all’?” This indicates that Macduff has more children beyond the one son who appears in the scene, which would add an unknown number to the total count of murders.
Of course, the above are not the only deaths that occur in the play, though the other deaths aren't usually characterized as murders. Shortly before the play begins, Macbeth kills the traitorous Macdonwald, and at the end of the play, he also kills Young Siward in the final battle. These could be considered murders, but are generally not called such because the deaths took place during battles and therefore fall under a different type of killing. If one was to count every death in the battles of Macbeth as a murder, it would be impossible to count how many murders truly take place.
Finally, one could argue that Macbeth’s death, when he fights with and is decapitated by Macduff, a murder as well. Macbeth was, directly or indirectly, responsible for every single other murder in Macbeth, and therefore his death is usually considered justified and necessary. Macbeth was murdering anyone and everyone if he thought they stood in his way to becoming king or were a threat to his keeping that title. His death was the only way to end the tragedies and hence is probably not qualified as a murder.