Over what period of time does Macbeth take place?

The exact length of time spanned by the events of Macbeth is unclear and is open to the interpretation of readers, audiences, directors, and actors. The 11th century Scottish king Mac Bethad, the nominal inspiration for Shakespeare's Macbeth, reigned for almost exactly 17 years following the death of his cousin and predecessor Duncan. But Shakespeare's play diverges from the historical chronicles in many major respects. The historical Duncan, for instance, was killed in battle against Macbeth's forces, not murdered in his bedchamber, and it seems clear that the events of Macbeth are meant to cover a much, much shorter duration than 17 years.

What we know for certain is that Macbeth reigns long enough for Malcolm and later Macduff to flee from Scotland to England and then return to Scotland accompanied by the English forces, and for Macbeth himself to perpetrate a considerable amount of harm and violence; he is referred to many times in the latter part of the play as a "tyrant," and in Act IV Scene 3, Malcolm laments "I think our country sinks beneath the  yoke; / It weeps, it bleeds; and each new day a gash / Is added to her wounds." The play is Shakespeare's shortest tragedy, and a guiding principle of its construction is one of terrifying economy and velocity, collapsing the thought and the action, the event and the consequence, into one. The Hungarian film director Bela Tarr conveyed this sense of nightmarish compression by staging almost the entirety of his TV production of the play in a single, highly mobile take, telescoping intervals in the story through cleverly executed in-camera time jumps. I'm linking to a detailed analysis of the play's temporal cues, which estimates the maximum duration of its narrative at several weeks. But it's important to remember that Shakespeare was notoriously free and haphazard about matters of chronology and narrative precision, and the textual clues of Macbeth offer at times contradictory indications about the time scheme of the play. The literal "in-world" duration of the action is of secondary importance to the creeping, dreamlike atmosphere of unreality, of time rapidly running out and the walls of the world closing in, created in the minds of both characters and spectators.