Tournament seeding tool

Paste names with ratings and get the seed list, the standard seed positions, the first-round pairings with byes for the top seeds, and the matches you would see if every favourite won.

Write “Name, rating” (a comma, space or semicolon before the number all work). Entrants without a rating are seeded last, in list order. With no ratings at all, list order is the seeding.

What does the number mean?

Seeding

Entrants
12
Bracket size
16
Byes
4
Rounds
4
Seeds and first-round opponents
SeedNameRatingRound 1
1Nova1912Bye
2Blaze1854Bye
3Kestrel1790Bye
4Orion1745Bye
5Vortex1701#12 Drift
6Lynx1688#11 Saber
7Ember1640#10 Pixel
8Rook1602#9 Comet
9Comet1577#8 Rook
10Pixel1540#7 Ember
11Saber1502#6 Lynx
12Drift1466#5 Vortex

Bracket order, top to bottom

Round of 16

  1. 1 Nova vs BYE
  2. 8 Rook vs 9 Comet
  3. 4 Orion vs BYE
  4. 5 Vortex vs 12 Drift
  5. 2 Blaze vs BYE
  6. 7 Ember vs 10 Pixel
  7. 3 Kestrel vs BYE
  8. 6 Lynx vs 11 Saber

If the higher seed wins every match

Quarterfinals

  1. 1 Nova vs 8 Rook
  2. 4 Orion vs 5 Vortex
  3. 2 Blaze vs 7 Ember
  4. 3 Kestrel vs 6 Lynx

Semifinals

  1. 1 Nova vs 4 Orion
  2. 2 Blaze vs 3 Kestrel

Final

  1. 1 Nova vs 2 Blaze

Standard placement: adjacent seeds add up to bracket size + 1 in round one (1 v 16, 2 v 15 and so on), and the top seeds are kept apart for as long as possible. Byes go to the highest seeds. Upsets change who meets whom in later rounds; the second list only shows the path if every favourite wins.

How standard seeding works

Take the entrants in order of strength. Then build the bracket by folding: the bracket for two entrants is [1, 2]. To double it to four, put each seed next to the seed that makes the pair add up to five, giving [1, 4, 2, 3]. Double again and every pair adds up to nine: [1, 8, 4, 5, 2, 7, 3, 6]. Repeat until the bracket is the next power of two at or above your field size. Adjacent slots play each other in round one, and the winners of neighbouring matches meet in round two, and so on.

Two properties fall out of this. First, in round one the top seed always plays the bottom seed and every match adds up to the bracket size plus one. Second, the strongest players are kept apart as long as possible: seeds 1 and 2 can only meet in the final, seeds 1 to 4 can meet no earlier than the semifinals, and seeds 1 to 8 no earlier than the quarterfinals. If every favourite wins, the quarterfinals are 1 v 8, 4 v 5, 2 v 7 and 3 v 6.

Byes: what happens when the field is not a power of two

A single-elimination bracket has to be a power of two, so any other field size leaves empty slots. Those empty slots are byes, and standard seeding puts them opposite the highest seeds. With 12 entrants the bracket has 16 slots and 4 byes, and seeds 1, 2, 3 and 4 skip round one. The tool shows this in the first-round list (a seed against BYE) and in the table (“Bye” in the Round 1 column). Nobody can get a bye in a later round, and no match ever has two byes.

Bracket size and byes by field size
EntrantsBracket sizeByesSeeds with a bye
5831–3
121641–4
2032121–12
3364311–31

Picking the ratings

The seeding is only as fair as the numbers it starts from. Ratings from a recent, comparable source (last season’s standings, a qualifier, an Elo table you maintain yourself) work best. Old results, or ranks from a different game, do not. If you have nothing reliable, leave the ratings out and use your list order, or draw at random; a made-up seeding is worse than none because players trust it. Publish the method with the bracket: which ratings, taken on what date, and how ties were broken. That takes a paragraph and prevents most arguments.

Ties deserve a rule of their own. When two entrants share a rating, the tool keeps your list order so the output is stable, but stability is not fairness. If the tie decides a bye or a match against seed 1, settle it by something the players agreed to in advance.

What seeding does not do

Seeding reduces the chance of lopsided early rounds; it does not remove luck. A bracket is decided by upsets as much as by strength, which is why the “if the higher seed wins every match” list is only a path and not a prediction. Seeding also cannot protect against a strong entrant who is under-rated because they are new. If that matters to your event, run a short qualifier or a Swiss stage first, then seed the knockout from the results. The Swiss pairing calculator does that first stage, and thebracket generator draws the knockout once the seeds are set.

Frequently asked questions

What is seeding?

Seeding ranks the entrants before the bracket is drawn, best first, and places them so the strongest do not meet early. Seed 1 is the top-ranked entrant. The point is that a bracket where the top two players meet in round one produces a worse final than one where they can only meet in the final.

Why does seed 1 play the lowest seed?

Because standard placement pairs seeds so that they add up to the bracket size plus one: 1 v 16, 2 v 15, 3 v 14 and so on in a 16-slot bracket. That gives the best seeds the easiest opening matches and puts the strongest opponents on the far side of the bracket.

Who gets the byes?

The highest seeds. A bracket is always a power of two, so 12 entrants play in 16 slots with 4 byes, and seeds 1 to 4 skip round one. The bye is a reward for a better rating, and it only exists in round one.

How are tied ratings handled?

They keep your list order and the tool marks them with a tie tag. That is only a placeholder: if the tie decides who gets a bye, settle it with a rule you announce in advance, such as head-to-head result, most recent event or a coin flip, then reorder the list.

Where do the ratings come from?

From wherever you trust: a previous event, a league table, a qualifier, an Elo rating you maintain or an in-game rank. The tool only sorts them. Ratings from different sources are not comparable, so do not mix a rank from one game with points from another.

My numbers are ranks (1 is best). Can I use them?

Yes. Choose “Lower is better” and the tool sorts ascending, so rank 1 becomes seed 1. Entrants without a number are always seeded last.

Can I keep teammates or clubmates apart in round one?

This tool does not do that. If two entrants must not meet early, swap their positions by hand after seeding, keeping the byes with the top seeds, and announce that rule before the event so nobody thinks the draw was fixed.

Does this work for double elimination?

The winners bracket of a double-elimination event uses the same seeding, so the seed list and first-round pairings apply. The losers bracket is filled by whoever drops down. The bracket generator draws both.