Tennis rules & scoring.

Inside a single game, tennis points are called by these names, in order: 0 (love), 15, 30, 40, game. The jump from 40 to "game" only happens if the opponent is on 30 or lower. If both players reach 40, the game is at deuce (covered in the next section).

The 15/30/40 names are a historical leftover from medieval French tennis played on a clock face — 15, 30, 45, reduced to 40 later for easier pronunciation. Nobody uses the clock any more, but the names stuck. "Love" meaning zero is widely believed to come from the French word l'œuf (egg), because a zero on a scoreboard looks like an egg, although the etymology is disputed.

Important: those point names only apply inside a game. Games inside a set, and sets inside a match, are counted using ordinary numbers (1, 2, 3…).

When both players reach 40-40, the score is called deuce. From deuce, you cannot win the game with a single point — you have to win two points in a row.

• — The first point won from deuce is called "advantage".
• — If the server wins it, the score is "ad-in" (advantage server).
• — If the receiver wins it, the score is "ad-out" (advantage receiver).
• — If the player with advantage wins the next point, they win the game.
• — If they lose it, the score returns to deuce and the process repeats.

A single game can therefore go on indefinitely in principle — the longest recorded game in professional tennis lasted over 30 minutes and more than 80 strokes across many deuces. This is one of the reasons no-ad scoring (section 9) exists for formats that need matches to finish on a clock.

Games are grouped into sets. To win a set, a player must win at least 6 games and lead by a margin of 2. So 6-3, 6-4 and 6-0 are all winning set scores. But 6-5 is not a set — the trailing player still has a chance to level at 6-6, at which point the rules say you have to play either one more game (if using advantage sets) or, far more commonly in modern tennis, a tiebreak.

Almost all professional and recreational tennis now uses the tiebreak at 6-6 rule. The exception historically was Wimbledon, which for decades played out indefinite final sets, but this was eventually changed. The modern Grand Slam rule (since 2022) is a tiebreak to 10 at 6-6 in the final set across all four majors.

Between sets, players get 2 minutes to sit down, drink water, and change ends.

A standard tiebreak is played to 7 points, win by 2. The scoring is simple counting — 1, 2, 3… — not 15/30/40. So a player can win a tiebreak 7-3, 7-4, 7-5, or 8-6, 9-7, 10-8, etc. You cannot win it 7-6; you keep going until one player is two clear.

Service in a tiebreak is a little fiddly. The player who was due to serve the next game begins by serving just one point. Their opponent then serves the next two points, and from there on service alternates in pairs of two. Players also change ends every 6 total points (so after points 6, 12, 18…).

Grand Slam final-set tiebreaks are now played to 10 points, win by 2 instead of 7. This gives the players more runway at the end of an epic match while still forcing a finish on a clock.

A tennis match is a best-of-3 or best-of-5 sets contest. Best of 3 is the default for women's Grand Slam singles, all tour-level doubles, and almost every recreational, club, and amateur match. Best of 5 is reserved for men's singles and doubles at Grand Slams and a handful of Davis Cup ties — the first player to win 3 sets wins the match.

Because the set is already quite long (6+ games, each of which can go to deuce), tennis is a slow sport relative to badminton or pickleball. Short best-of-3 matches can still run 90 minutes. Long best-of-5 Grand Slam matches have on occasion run over 5 hours.

Every point starts with a serve. Serving alternates game-by-game — one player serves an entire game, then the other serves the next, and so on. The server gets two attempts per point. A missed first serve is called a "fault"; you then get a "second serve". If the second serve is also a fault, that's a double fault and the receiver wins the point.

• — The server must stand behind the baseline, between the centre mark and the sideline.
• — Neither foot may touch or cross the baseline before contact — this is a "foot fault".
• — The ball must land in the diagonally opposite service box, beyond the net.
• — A serve that touches the net and still lands in is called a "let" — the serve is replayed with no penalty (and doesn't count against your two attempts).
• — If the ball touches the net and misses the service box, it counts as a fault.

The server alternates sides after each point — right side (deuce court) when the total of points played is even, left side (ad court) when it's odd. At the start of a new game, you're back on the deuce court.

Within a game, the server's score is called first. So "30-15" means the server has 30 and the receiver has 15. At the start of a game the score is "love-all". When both players are tied on the same number, the call is just the number and then "all": "15-all", "30-all". 40-40 becomes deuce.

Before each new game, the server announces the set score, which is always called in the order: games won by whoever served first in the set, then by the other player. So if you're serving to open the second game of a set and you're 1-0 up, the call is "1-love, new game".

The tennis court is 78 feet long and 27 feet wide for singles. For doubles, the court widens to 36 feet — the two tramline strips on either side come into play. The baseline, net, and service boxes are identical in both formats; only the sidelines change.

Doubles adds a second partner on each side, so there are four players on the court. Doubles service rotates among all four players — first the A1 player serves, then B1, then A2, then B2, then back to A1, and so on. The receiving partner positions are fixed for the duration of a set: whoever starts as the deuce-court receiver stays there.

No-ad scoring is a shortened format used by college tennis, many social and mixed leagues, World TeamTennis, and increasingly by ATP doubles. The rule is simple: at deuce, a single point decides the game. There is no advantage, no second deuce, no fifteen-minute marathon game. Sudden death, loser goes home.

The receiver chooses which side of the court to return the deciding point from. Everything else about the game remains the same. It's a surprisingly different experience to play — every deuce suddenly carries match-point intensity — and it cuts match times meaningfully.