How tennis scoring works: points, games, sets and tiebreaks

Tennis counts like no other sport. A player can win more points than the opponent and still lose the match, 40-30 means three points to two, and "love" means nothing at all. The system has only four layers, though, and the rules that define them fit on two pages of the ITF's Rules of Tennis, quoted here from Tennis Canada's 2026 edition, which reproduces them with local notes.

How does tennis scoring work?

Points make games, games make sets, and sets make the match. At each layer the winner needs a small majority plus a margin:

• A game goes to the first player to win four points, provided they lead by two. That is the standard advantage game; professional doubles on the ATP and WTA tours uses no-ad scoring, where a single deciding point at deuce settles the game.
• A set goes to the first player to win six games, provided they lead by two, or to the winner of a tiebreak at six games all.
• A match is the best of three sets or the best of five.

In a standard game one player serves throughout, and at the end of it the receiver becomes the server for the next (Rule 14); the tiebreak is the exception, with service changing after the first point and then every two points. Because the server has the upper hand at the top level, the logic of a set turns on who wins games on the other player's serve.

Why is tennis scoring love, 15, 30, 40?

Within a game, points are not counted 1, 2, 3. Rule 5 lists the calls: no points is "love", the first point "15", the second "30", the third "40", and the fourth wins the game. The server's score is called first, so 40-15 means the server is one point from the game and 15-40 means the receiver is. When both players have one or two points, the score is "15 all" or "30 all".

What is deuce in tennis?

At three points each the score is not "40 all" but deuce. From deuce a player has to win two consecutive points. Win one and the score is "advantage"; win the next and the game is over. Lose the next and it is deuce again, with no limit on how often that can happen.

Why is tennis scoring 15, 30, 40 and not 1, 2, 3?

Nobody knows for certain, and any explanation offered as fact deserves suspicion. Wikipedia's survey of the question traces the earliest surviving reference to a 1435 ballad by Charles d'Orléans that mentions "quarante cinq", 45; people were already guessing at the origin in the 1550s. Three explanations recur.

The clock face: a quarter turn of the hand per point, 15, 30, 45, with 60 ending the game, and 45 later shortened to 40 so that deuce could move the hand to 50 and then 60. The objection is that medieval clocks generally showed hours only; minute hands were not standard until about 1690. The jeu de paume court: in the French ancestor of tennis, the server supposedly advanced 15 feet after each point, then 15, then 10, on a 90-foot court, but there is no evidence courts had a standard length. Base-60 counting: medieval France counted money and measures in sixties, and the game was heavily wagered on, so four steps of 15 may simply have felt natural.

The word love has its own guesses: "playing for love", meaning for nothing rather than for a stake; the French l'œuf, an egg shaped like a zero; or a Dutch phrase for doing something for praise rather than money. None has documentary proof either. The honest summary is that tennis inherited its counting from a medieval game and the paperwork is lost.

What is a break of serve?

Because one player serves for the whole game, every game has an expected winner. Winning a game on your own serve is a hold; winning one as the receiver is a break. A break point is a point that, if the receiver wins it, produces a break, so 30-40 or advantage to the receiver; 15-40 is two break points and love-40 three. Wikipedia's glossary of tennis terms puts the significance plainly: at a high level of play the server is more likely to win the game, so breaks are often the key moments of a match.

This is why commentators say a set is "on serve": neither player has broken more often than the other, and someone still has to break to win it outright. It is also why the serving order matters more than the score: a player who leads 5-4 and is about to serve can take the set by holding, one who leads 5-4 while the opponent serves needs another break.

How do you win a set?

Rule 6 gives two methods. In an advantage set, the first player to six games wins, provided they lead by two, and the set continues indefinitely until someone does. In a tiebreak set the same applies up to six games all, at which point a tiebreak game decides the set and the score is recorded as 7-6. Players change ends after the first game and every odd game thereafter (Rule 10).

The advantage set survived longest in the deciding set at the Grand Slam tournaments, where it produced the longest match ever played: John Isner beat Nicolas Mahut at Wimbledon in 2010 by 70-68 in the fifth set, 11 hours and 5 minutes over three days.

Tennis tiebreak rules

A tiebreak is a single game with its own counting. Points are called "zero", "one", "two" and so on, and the first player to seven wins the game and the set, provided they lead by two; otherwise the tiebreak continues until someone does. The player whose turn it was to serve serves the first point. The opponent serves the next two, and from there the players alternate two points each. They change ends after every six points, and whoever served first in the tiebreak receives first in the next set. The number in brackets on a scoreline is the loser's tiebreak score: 7-6 (5) was decided 7-5, and 7-6 (8) went to 10-8.

Since 2022 all four Grand Slam tournaments have used a longer version when the final set reaches six games all. The Grand Slam Board announced the change on 16 March 2022 as a trial beginning at that year's Roland-Garros: at 6-6 in the deciding set, the match goes to the first player to win 10 points with a margin of two. The 2026 Grand Slam Rule Book now states it as the rule. Until then each tournament had its own rule. The US Open had decided the fifth set with a tiebreak since 1970, the Australian Open adopted the 10-point version in 2019, Wimbledon introduced a seven-point tiebreak at 12-12 the same year, the score at which Novak Djokovic beat Roger Federer in the 2019 final, and Roland-Garros had no final-set tiebreak at all.

The 10-point format has a second role: in doubles on both professional tours, a 10-point match tiebreak replaces the third set entirely when the first two are split (ATP Rulebook 1.02 B; WTA Rulebook, scoring system).

How many sets in tennis?

Rule 7 allows two formats: best of three sets, where a player needs two, and best of five, where a player needs three. Who plays which is decided by the tours and tournaments, not by the rules of the game.

On the ATP Tour every singles match, including finals and the season-ending ATP Finals, is the best of three tiebreak sets (ATP Rulebook 1.02 B and 4.01 A). On the WTA Tour every singles match is the best of three tiebreak sets. At the four Grand Slam tournaments, the Grand Slam Rule Book requires all men's singles main-draw matches to be the best of five sets, with every other match, women's singles and all doubles included, the best of three unless a tournament decides otherwise. Men's singles at the majors is therefore the only place in the modern game where a player must win three sets.

How long is a tennis match?

There is no fixed length. The best figure for the top end comes from The Athletic's analysis of ATP data, as reported by Front Office Sports: the average men's Grand Slam match, played over the best of five sets, rose from 2 hours 21 minutes in 1999 to 2 hours 54 minutes in 2023. Tour matches, best of three, are shorter; the longest at an ATP Tour event in Wikipedia's list of records, Rafael Nadal over Djokovic in Madrid in 2009, took 4 hours 3 minutes.

The 2026 US Open shows the spread. Alexander Zverev's straight-sets fourth-round win over Luciano Darderi took 2 hours 31 minutes; his five-set first-round win over Lorenzo Sonego had taken 4 hours 53 minutes and finished at 1:55 a.m., the first of the top seed's late nights in New York. Djokovic's five-set defeat by Mariano Navone lasted 4 hours 36 minutes, the longest first-round match of his Grand Slam career and his first opening-round defeat at the US Open. Matches of that length are why several New York night sessions finished after 2 a.m., to the Associated Press's reports of empty seats and tired players.

The records set the ceiling. Below Isner's 11 hours, the longest Grand Slam final is Djokovic's win over Nadal at the 2012 Australian Open, 5 hours 53 minutes, and the 2025 Roland-Garros final between Carlos Alcaraz and Jannik Sinner ran 5 hours 29 minutes.

Put the layers together and a line such as 6-4, 3-6, 7-6 (4) reads itself: sixteen games each, and a clear winner, because tennis does not reward the player who wins the most points but the one who wins the right ones.