The numbers by event
Club sets run one to three hours per slot — warm-up, peak and close are different crafts, and all-night-long (open to close, one DJ) is its own discipline. Wedding evening receptions typically carry four to six hours of music. Corporate events usually need coverage from doors to carriages with the dance floor concentrated in the last two to three hours. Festival slots run 45 minutes to 90 minutes and are shaped by the bill around them. Brand activations can mean doors-open-to-doors-closed coverage across a full day, planned in arcs with scheduled breathing room.
Why the arc matters more than the hours
A four-hour set is not four one-hour sets in a row. Energy has to be spent like a budget: build too early and the floor is exhausted before the night peaks; hold back too long and it never ignites. When you brief a DJ, the useful information is not just “play for five hours” but where the peak should land and what has to happen around it — speeches, awards, last trains.
One good DJ across the whole night usually beats two or three in relay for private and corporate floors, because the arc lives in one head. Clubs are the exception: a bill of DJs is the format, and handovers done properly are part of the craft.