Seeding creates the first round
A single-elimination bracket needs a power-of-two number of slots: 2, 4, 8, 16, 32, or 64. This tool shuffles the entrant names locally and pairs adjacent positions. If the entrant count is not a power of two, it fills the unused slots with BYE markers. A bye advances the paired entrant without a played first-round match. The output deliberately covers first-round seeding only; later winners depend on actual results.
Bracket arithmetic
For N entrants, choose the smallest power of two S such that S ≥ N. The number of first-round pairings is S/2 and the number of byes is S−N. With 13 entrants, S is 16, so there are eight first-round slots and three byes. The tournament still needs 12 played matches overall to produce one winner, because every match eliminates exactly one entrant. The bracket size changes presentation, not the fundamental N−1 eliminations.
Worked example
Enter Alex, Blair, Casey, Drew, Eden, Finn, Gia, Hal, Inez, Jae, Kai, Lou, and Miro. The tool uses a 16-slot bracket. One possible first round is Alex vs Gia, BYE vs Miro, Blair vs Finn, and so on. The position paired with BYE advances; it is not a missing match that can later receive an extra opponent. Write winners into the next bracket round only after every relevant opening pairing is resolved.
Fairness choices
Random seeding gives every entrant an equal chance of every bracket position. It does not balance skill, geography, club affiliation, or rematches. If the event has ranked seeds, enter a designed bracket instead; randomizing would discard a stated competitive policy. For a casual event, random seeding is easy to explain because no organizer chooses opponents. Publish the generated pairs before play begins so that rerunning the tool cannot become an invisible redraw after someone dislikes a matchup.
Input and operational limits
Put one name per line, or separate names with commas. Empty lines are ignored and duplicate text is treated as separate entrants, so distinguish two people named Sam with surnames or labels. The tool accepts 2 through 64 entries to keep the first-round result readable. It does not track scores, loser brackets, round-robin scheduling, or double elimination. Those formats have different structures: a double-elimination bracket must account for a second loss path, not merely add more random pairs.
How it differs
A team splitter distributes people into groups of a specified size; it may produce several simultaneous teams with no elimination tree. This bracket tool creates opposing pairs and explicit byes for one knockout path. A weighted picker chooses one result with unequal odds; tournament seeding gives every entered name an equal chance of every initial slot. Use it once at event setup, then preserve the result as the tournament record.
From pairings to a completed event
Copy the first-round pairs into a visible bracket numbered by slot. The winner of slots 1 and 2 meets in the next round, the winner of slots 3 and 4 meets, and so on; this prevents an organizer from improvising later opponents. If a BYE occupies one half of a pair, advance the other entrant into the named next-round slot before play begins. With an odd number of entrants, random placement makes the recipients of byes random too. A seeded tournament may instead assign byes to high seeds, but that is a different fairness rule. Allow enough rounds: an eight-slot bracket has three rounds, while a sixteen-slot bracket has four. Collect tie-breaking rules, game length, and absence policy before the draw. This generator does not resolve disputes or choose winners; it makes the initial allocation transparent.
Fix the bracket rule before the draw
With 13 entrants in 16 slots, three people receive byes and twelve played matches are needed to leave one winner. Decide before shuffling whether an absence forfeits, a late arrival can replace a bye, and how ties are settled. Changing one of those policies after the pairs are public changes the competition; random placement cannot make that later decision fair.