Random tournament draw
For a club night, an office competition or anything else where nobody has a ranking. The order is shuffled properly, not sorted and jiggled.
The bracket
Quarter-finals
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DunmoreBellweather
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GrantonHalstead
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AshfordFernhill
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CastletonEastfield
Semi-finals
Final
Winner
When random beats seeded
Seeding exists to keep the best entrants apart until late, which is worth doing when there is a ranking everybody accepts. Where there is not — a Friday night at a club, eight people in an office, a family tournament — a seeded draw is somebody guessing at an order and then defending it.
A random draw removes that entirely. It is also the fairer answer when the field is genuinely unknown to each other, because a guessed seeding is worse than none: it distributes an error systematically rather than at random.
The one thing a random draw cannot do is stop two strong entrants meeting in the first round. If that matters more than the appearance of fairness, seed it.
What "random" has to mean
A Fisher-Yates shuffle over the whole list, which gives every ordering exactly the same chance. The alternative most code reaches for — sorting with a random comparator — does not: it produces a distribution that is measurably biased towards leaving items near where they started, and on a small field that bias is visible.
The draw is shuffled once, in your browser, using its own random source. Nothing is sent anywhere and nothing is recorded, which also means the draw cannot be reproduced afterwards: print it, or photograph it, before you close the tab.
Press the button again and you get a genuinely different draw. That is a feature at the point of drawing and a hazard afterwards, so the sheet is the record.
Common questions
How do you do a random tournament draw?
Put every entrant in the list and press draw. The order is shuffled with a Fisher-Yates shuffle, which gives every possible draw the same chance, and the result is laid into the bracket in the order it came out.
Is a random draw fairer than a seeded one?
It is fairer when nobody agrees on a ranking, because a guessed seeding distributes its error systematically. Where a ranking exists and is trusted, seeding is fairer: it stops the two best entrants meeting in round one by accident.
Can I redo the draw?
Press the button again for a completely new one. Nothing is stored, so the previous draw is gone — print or photograph a draw before you redo it.