A standard professional sumo tournament lasts 15 days.
These tournaments are called honbasho, and the top-division schedule normally gives each wrestler one bout per day. The wrestler with the best record at the end wins the division championship. A 15-day tournament therefore creates a longer test of consistency than a single-elimination competition.
The daily schedule begins with lower-ranked wrestlers and progresses toward the top division. The highest-ranked bouts take place late in the afternoon, after which the champion is determined from the final records. If two or more wrestlers finish tied for the best mark, additional playoff bouts can decide the winner.
Japan holds six major tournaments each year, so the 15-day format is repeated in different cities and seasons. The system also allows wrestlers’ rankings to change according to performance. A winning record generally helps a wrestler rise, while a losing record can cause demotion, with special rules applying to certain upper ranks.