These are the tie breaks available in WinTD that comply with US Chess rules.

 

Individual Tournaments

For individual Swiss System tournaments, the US Chess recommends that you use the following tie-breaks in the order shown:

 

1. Modified Median

2. Solkoff

3. Sonneborn-Berger

4. Cumulative

 

(If any order other than this is used in a US Chess-rated tournament, that information is supposed to be posted). On the prize lists, WinTD will rank players first based upon score. Within each score group, they will be ranked based upon the first tie-break you select. In any groups which are still tied, the second tie-break will be applied, etc. Players who are still tied (that is, their scores and first and second tie-breaks are all identical) will be ranked by the third tie-break, etc.

 

If you have two players tied through all five of those (rare, but possible, particularly for perfect scores), any further tie breaks are scarcely better than a coin flip.

Solkoff/Median/Modified Median

A player's Solkoff is the sum of his or her opponents' scores. The Modified Median and the Median are similar to the Solkoff, but the "least meaningful" results are left out. For all scores for Median, and for even scores for the Modified Median, both the highest and lowest (two highest and two lowest for tournaments with nine or more rounds) are discarded. Modified Median differs from Median in its handling of plus and minus scores. For players with plus scores, the lowest opponent's score is discarded (lowest two scores for nine or more rounds). For players with minus scores, the highest score (two scores for nine or more) is discarded. For players with even scores, both high and low scores are discarded. For instance, suppose two players with 4-1 scores met players who ended with the following scores:

 

Player A: 0,3,3,4,5

Player B: 3,2,5,3,3

 

Player A's Solkoff tie-break is 0+3+3+4+5=15, Player B's is 3+2+5+3+3=16. Player A's Modified Median is 3+3+4+5=15 (discard the 0) and Player B's is 3+5+3+3=14 (discard the 2). Player A's Median is 3+3+4=10, Player B's is 3+3+3=9. If we use Modified Median or Median first, A ranks higher than B; if we use Solkoff first, B ranks higher than A.

 

Cumulative/Adjusted Cumulative/Opponent's Cumulative

A player's Cumulative is the sum of his or her scores at the ends of each round. If Player A won his first four and lost the last round, and Player B won two, lost the third round, and won the last two, the players scores at the ends of the rounds are:

 

Player A: 1,2,3,4,4

Player B: 1,2,2,3,4

 

Player A's cumulative is 1+2+3+4+4=14, Player B's is 1+2+2+3+4=12. The cumulative tie break measures strength of schedule indirectly. By Swiss System pairing rules, players who do not lose until later rounds (and thus have high cumulatives) will usually face tougher opponents than players who lose in early rounds (and thus have low cumulatives). The Adjusted Cumulative is the Cumulative score minus the first round's contribution, which is useful if you use accelerated pairings (where the first and second round pairings are different from standard Swiss), and might also be useful if there are many unplayed games in the first round.

 

Opponent's Cumulative is the sum of the cumulatives of a player's opponents. This only very indirectly measures the strength of opposition. The one advantage it has is that, because of the number of results that enter into it, it is highly likely to be different for most players in a tie, and so might be useful as a final tie break.

 

Sonneborn-Berger

The Sonneborn-Berger is the sum of 1 x (scores of opponents defeated) + .5 x (scores of opponents drawn). Compared with the Solkoff, this rewards scores against high-scoring opponents but does not penalize as severely failures to win against low-scoring opponents. It's commonly used as a tie break in Round Robin tournaments simply because it is one of the few that actually can break ties in a Round Robin. (Solkoff, Median and Modified Median will all be the same for players who tie in a Round Robin; Cumulative-based tie breaks make no sense since the order of games is basically random).

 

Kashdan/Played Black

A player's Kashdan is 2 x wins + 1 x draws. In effect, this makes a win and a loss worth more, for tie break purposes, than two draws. (It's basically equivalent to counting wins).

 

The Played Black option simply counts number of games played black.

 

Percentage Score

The Percentage Score is simply a player's score divided by the number of games played, multiplied by 100. For example, 5 points in 5 games played gives 100%, while 3 points in 6 games gives 50%. The most common use for this is as a tie break for board prizes in a (long) team tournament.

 

Competition Average

Competition Average is the average of the ratings of a player's rated opponents. Unrateds are left out of the average, so this should not be used in tournaments with unrated players.

 

Head-to-Head Limited

Head-to-Head General

Head-to-Head tie breaks aren't used often in large Swiss System tournaments since meetings between the top players aren't common (and many of those few end in draws). The Head-to-Head tie break is the net score for all players in a tie in games against the others in the tie, so if one player goes 3-1, that is +2, while 1-0 is +1. Head-to-Head Limited (which is not listed in the US Chess rule book) is only non-zero if all players involved in a tie play each other; if they don't, it's zero for all (and thus doesn't break any ties). Head-to-Head General is used regardless of how many games there are among tied players.

 

Random

This is basically a computerized coin flip. It should only be used as a final tie break.

 

Combined Tournament Tie-breaks

Team awards for combined tournaments are broken using the same tie-break methods as individuals. WinTD ranks a team's players according to their scores and the combined team tie-breaks (which may be different from the individual tie breaks). It then sums the values of these for the number of players who make up a team and orders the teams accordingly. Note that a number of individual tie breaks are inappropriate for team purposes, in particular, Modified Median is not used. (Modified Median treats positive score groups differently from even and minus score groups and thus is not appropriate for breaking ties involving players with different scores).

 

Team A   Score Median Solkoff    S-B     Cum 

Player A1 5.0   8.50    13.50   13.50   15.00

Player A2 4.0   9.00    16.00   11.50   14.00

Player A3 3.0   8.00    11.00   10.50    7.00

 

Team B

Player B1 4.0   8.50    13.50   10.50   11.00

Player B2 4.0   8.50    13.50    8.50   13.00

Player B3 4.0   8.00    15.00   10.00   14.00

Player B4 4.0   7.00    13.50    8.50   13.00

 

If we count the top three scores and use the tie-breaks in the given order, the two teams' tie-breaks are

 

         Score  Median Solkoff   S-B     Cum

Team A   12.0    25.50   40.50   35.50    36.0

Team B   12.0    25.00   42.00   29.00    38.0

 

Team A finishes ahead of Team B because its top three players have a higher Median than Team B. If we had used Solkoff first in the order, then B would have finished ahead of A, which is why it's important to decide on the tie break order in advance. (Note that neither order is "wrong", but since tropies are indivisible you have to have a method to break the tie). Note that if you have players tied for the last "counting" score on the team, the same three (in this case) are used throughout the calculation for the team's tie breaks. If one has a higher median and another the higher Solkoff, the one with the higher median is still used to compute the Solkoff if the median is the first tie break.

 

Team v Team Tournament Tie Breaks

WinTD offers three tie-break systems used only for team vs team tournaments: US Amateur (Teams), Performance Index (Teams), and Game/Match Points (Teams). These are only used for team vs team section tie breaks and are unavailable (or ignored) for other types. The US Amateur Teams takes the sum of the points scored against in a match x that opponent's match score—if you score 3-1 against a team which was 4-2, the USAT tie break element is 3 x 4=12). The Performance Index is a weighted sum of the total game points and the team's Solkoff (see description below). Game/Match Points is the sum of total points won (game points) if you are basing placement on match results and the number of match points if you are basing placement on game points. It's possible to use some of the more standard tie breaks, such as Solkoff, but that will count a 2.5-1.5 match win the same as a 4-0. The simplest of the three special team tie breaks is Game/Match Points. It is not a good choice for a first tie breaker because it is likely to produce the opposite of the desired result—a team which faces weak opposition is likely to pile up more game points than a team facing tougher opponents.

 

The US Amateur Teams tie break is superior to those. It has two minor drawbacks: the individual games against a very weak opponent are unlikely to count much (they don't count at all against an opponent who gets 0 match points) and it tends to put too much weight on crushing wins against middle of the pack teams versus competitive matches with top teams. (4-0 against a team with a 2.5-3.5 record is worth more than 1.5-2.5 against a 6-0 team). The flip side of giving more tie break points to wins against high-scoring teams is that losses to high-scoring teams hurt more than losses to low-scoring teams.

 

The Performance Index is an experimental tie breaker (not in the rule book). It takes a weighted sum of the Solkoff and Game Points, with the weight on the Solkoff becoming higher as the number of rounds increases. It is based upon the following calculation: suppose a team scores S (out of G games) against an opponent who scores W match points in R rounds. Assign to this opponent a base performance value of 100+(W/R-1/2)(50+10R). (This is roughly 1/10 of the typical "rating" for such a performance if all teams had a prior rating of 1000—we divide the "rating" calculations by 10 to give it a scale more like other tie breakers, and to avoid confusion with the actual ratings). Add to this (S/G-1/2)*80 to get the performance index for this match. Take the average of these across all of the team's matches. (Unplayed rounds are treated as 0 scores against an opponent scoring 0, as they are in the other tie breakers). Since the sum of W's is the Solkoff and the sum of S's is Game Points, the result will be a weighted sum of Solkoff and Game Points. Unlike the USAT tie break, all games are equally valuable. It tends to rank teams pretty similarly to the USAT, but seems more likely than the USAT to place highly teams which lose to the top teams over those which lose to lower scoring teams.

 

WinTD also offers the IHSA (Teams) choice for use in Illinois High School Association tournaments.

 

Board in Team vs Team Tie Breaks

These are used to break ties for board prizes in team vs team tournaments. Because teams get paired, not players, the information in most of the standard individual tie breaks can be less valuable than usual. A good player on a weak team can pile up lots of wins without having to play any of the stronger players on his board. You can use standard tie breaks like Solkoff or Modified Median. The one new one that is only available for this is the Percentage Score, since, particularly in longer tournaments, players will sometimes sit out some rounds, so not everyone plays the same number of games. Note that this only applies to players who score the same number of points to start—6-0 (100%) beats 6-1 (86%). Some tournaments award prizes based upon percentage score ahead of points scored (7-0 is ahead of 8-1). WinTD will not directly compute board standings based upon that (which typically also requires specifying a minimum number of games, so 2-0 will not beat 8-1).

 

Copyright © 2026 Thomas Doan