The Dartboard: Setup and Dimensions
The standard dartboard used in all professional competition is known as the "clock" or "London" board. It is divided into 20 numbered segments, each separated by thin metal wire (or, on modern boards, razor-thin blades). The board also features an outer bullseye ring worth 25 points and an inner bullseye (the "bull") worth 50 points.
Each numbered segment contains four scoring areas. The main, larger bed scores the face value of that number. The thin outer ring, known as the double ring, scores twice the face value. The thin inner ring, roughly halfway between the bullseye and the outer edge, is the treble ring and scores three times the face value. This means the highest single-dart score on the board is treble 20, which scores 60 points.
Board Dimensions
A regulation dartboard has a diameter of 451mm (17.75 inches). The inner bull measures 12.7mm in diameter, whilst the outer bull measures 31.8mm. The treble ring and double ring are each 8mm wide. These measurements are standardised by both the Darts Regulation Authority (DRA) and the World Darts Federation (WDF) to ensure consistency across all levels of the sport.
Mounting Height
The dartboard must be hung so that the centre of the bullseye is exactly 1.73 metres (5 feet 8 inches) from the floor. This measurement is taken from the floor to the centre of the bull, and the board must be mounted flush against the wall with the 20 segment at the top, directly above the bullseye.
The Oche (Throwing Line)
The throwing line, commonly referred to as the "oche" (pronounced "ockey"), is positioned 2.37 metres (7 feet 9.25 inches) from the face of the dartboard, measured horizontally along the floor. A player must stand behind this line when throwing. The front foot may touch the oche but must not cross it. If a raised oche is used, the player's feet must remain behind the raised edge. In professional televised events, the oche is typically a raised platform.
The diagonal distance from the bullseye to the oche is 2.93 metres (9 feet 7.5 inches). This measurement serves as a useful cross-check when setting up a board to confirm both the height and throwing distance are correct.
The 501 Game: How It Works
The standard game of darts played in virtually all professional competition is 501. Each player begins with a score of 501 and takes turns throwing three darts per visit to the board. The score achieved with each throw is subtracted from the player's remaining total. The objective is to reduce the score from 501 to exactly zero, with the final dart landing in a double segment or the inner bullseye.
Starting the Game
In professional darts, there is no requirement to hit a double to begin scoring. Players may start reducing their total from 501 immediately with their first dart. This is known as a "straight start" or "double in not required." Some amateur and pub formats do require a double to begin scoring, but this is not used in PDC or televised competition.
The Double-Out Rule
The defining rule of 501 is that you must finish on a double. This means your final dart must land in one of the 20 double segments around the outside of the board, or in the inner bullseye (which counts as double 25). For example, if you have 32 remaining, you need to hit double 16 with your next dart to win the leg. If you have 50 remaining, you could hit the inner bullseye to check out.
This rule is what separates the casual player from the professional. It is not enough simply to score heavily; you must also be able to finish accurately on the doubles. The best players in the world maintain checkout percentages above 40%, meaning they successfully finish on a double more than four times out of every ten attempts.
The Bust Rule
If a player's score goes below zero, or reaches exactly one (since the lowest possible double is two), or reaches exactly zero without the final dart being a double, the player's turn is declared "bust." When this happens, the player's score reverts to what it was at the start of that turn, and the throw passes to the opponent.
For example, if a player has 32 remaining and hits a single 16 with the first dart (leaving 16), then hits a single 16 again with the second dart (which would leave zero but not via a double), the score is bust. The player goes back to 32, and the opponent throws next.
Similarly, if a player has 32 remaining and hits treble 20 (60) with the first dart, they have gone below zero and the turn is bust immediately. Any remaining darts in that visit are forfeit.
Scoring System in Detail
Single Segments
The main bed of each numbered segment scores the face value. Hitting the single 20 scores 20, single 19 scores 19, and so on down to single 1. These are the largest target areas on the board and form the foundation of consistent scoring.
Double Ring
The narrow outer ring scores double the face value of that segment. Double 20 scores 40, double 16 scores 32, double 10 scores 20, and so forth. The highest double is double 20 (40 points), and the lowest is double 1 (2 points). The double ring is crucial because it is required to finish a leg of 501.
Treble Ring
The narrow ring positioned roughly halfway between the bullseye and the double ring scores treble the face value. Treble 20 scores 60, treble 19 scores 57, treble 18 scores 54. The treble 20 is the most targeted segment on the board, as three treble 20s in a single visit score the maximum possible 180.
Bullseye
The outer bull (the larger green ring around the centre) scores 25 points. The inner bull (the smaller red circle at the very centre) scores 50 points and counts as a double for the purposes of checking out. In some amateur formats the outer bull also counts as a double, but in professional PDC darts, only the inner bull (50) counts as a double finish.
Maximum Score
The maximum score from a single visit of three darts is 180, achieved by hitting three treble 20s. This is one of the most celebrated moments in professional darts and is greeted by a call of "one hundred and eighty!" from the announcer. Top professionals regularly hit multiple 180s in a single match, with the best players averaging around one every two to three legs.
Sets vs Legs
Professional darts matches can be played in one of two primary formats: legs or sets.
Legs Format
In a legs format, the match is played as a straight race to a specified number of legs. For instance, a "best of 11 legs" match requires the first player to win 6 legs to claim the match. Each leg is a single game of 501. This format is used in most PDC ranking events, including Players Championship events, European Tour events, and the World Matchplay.
Sets Format
The sets format adds an additional layer. A set is typically the best of five legs (first to three), and the match is played as a race to a specified number of sets. For example, a "best of 5 sets" match requires a player to win 3 sets, with each set being the best of 5 legs. This is the format used at the PDC World Championship. The sets format tends to produce longer, more dramatic matches, as a player who loses a set must win the next set from scratch.
At the World Championship, the final is played over the best of 13 sets, meaning the winner must claim 7 sets to lift the Sid Waddell Trophy. Earlier rounds use shorter formats, typically best of 5 sets in the first round, increasing as the tournament progresses.
Throw Order
In each leg, one player throws first and the other throws second. The player who throws first has a natural advantage because they always have the first opportunity to check out. In a sets format, the right to throw first alternates between legs within a set, and the player who began the previous set throwing second will begin the next set throwing first. In legs-only formats, the throw typically alternates from leg to leg.
Before the match begins, a bull-off determines who throws first. Each player throws a single dart at the bullseye, and the player whose dart lands closest to the centre gets to choose whether to throw first or second. Almost all players elect to throw first.
Common Fouls and Rules Infractions
Stepping Over the Oche
A player must remain behind the oche at the point of release. If any part of the player's foot is beyond the front edge of the oche when the dart leaves the hand, the throw does not count. In professional competition, this is monitored by a referee, though it is rarely called because players are conditioned to respect the line. In casual play, this rule is often enforced on the honour system.
Darts Falling Out of the Board
A dart must remain in the board until the player's score has been recorded by the referee or scorer. If a dart bounces out of the board or falls out before the score is taken, it does not count. This means the player loses the potential score from that dart but does not face any additional penalty. Bounce-outs can be particularly costly during a checkout attempt.
Touching Darts in the Board
A player must not touch any dart that is in the board until all three darts have been thrown and the score has been called. If a player removes a dart from the board before the score is recorded, only the darts that were scored before the removal count.
Time Limits
In professional PDC events, there is no formal shot clock, though players are expected to maintain a reasonable pace. The referee has the authority to warn and ultimately penalise a player for slow play. In practice, most professional matches flow at a brisk pace, with players typically completing a visit in under 30 seconds.
Etiquette and Sportsmanship
Darts has a strong tradition of sportsmanship and courtesy. Though these are not formal rules, they are widely observed at all levels of the game.
Standing Position
When it is your opponent's turn to throw, you should stand well to the side and slightly behind the oche. Standing in the thrower's peripheral vision or directly behind them is considered poor etiquette. In professional events, the non-throwing player stands to one side of the stage, clearly out of the thrower's line of sight.
Noise and Distraction
Players are expected not to make unnecessary noise or movements whilst their opponent is throwing. In televised events, the crowd is generally free to make noise between darts, but sustained heckling or deliberate distraction during a throw is frowned upon. Referees have the authority to pause play if crowd behaviour becomes disruptive.
Handshake
It is customary for players to shake hands both before and after a match. This is a deeply ingrained tradition in darts and is observed at every level from pub matches to World Championship finals. Refusing a handshake is considered a serious breach of etiquette.
Acknowledging Good Play
Players commonly acknowledge an opponent's good darts with a nod or a verbal acknowledgement. When an opponent hits a 180 or completes a brilliant checkout, it is customary to offer a brief recognition. This mutual respect between competitors is one of the sport's most admirable qualities.
Additional Rules for Specific Formats
301 and Other Short Games
Whilst 501 is the standard for professional play, shorter formats such as 301 are popular in amateur and pub darts. In 301, players start at 301 and must reach zero on a double, just as in 501. Some 301 formats require a double to start as well as to finish, adding an extra challenge. The shorter starting score means that heavy scoring is less important and accurate doubling becomes the primary skill.
Cricket (American Format)
Cricket is a popular game in North America where players must "close" the numbers 15 through 20 and the bullseye by hitting each number three times (any combination of singles, doubles, and trebles). Once a player has closed a number, any further hits on that number score points, provided the opponent has not also closed it. The game ends when one player has closed all numbers and the bullseye, and that player also has the higher (or equal) points total. Cricket is not played in professional PDC competition but remains hugely popular in recreational settings.
Team Events
In team events such as the World Cup of Darts, pairs matches use a slightly different format. In doubles matches, teammates take turns throwing legs rather than each throwing in the same leg. In the singles matches, standard 501 rules apply. The team format requires both players to be in good form, as carrying a partner is extremely difficult at the highest level.
The Role of the Referee
In professional darts, a referee oversees every match. The referee's duties include calling the score after each visit, monitoring the oche for foot faults, determining whether darts have landed in the correct segment when there is a dispute, and maintaining the overall pace and order of the match. The referee's call is final in all scoring matters.
Referees also announce the remaining score to both players and the audience, calculate checkout combinations, and signal to the crowd when a player is on a finish. The best referees, such as Russ Bray and George Noble, become well known in their own right and add significantly to the atmosphere of televised events.
Summary
The rules of darts are straightforward but nuanced. At its core, the game is simple: throw three darts, subtract from 501, finish on a double. Yet within that framework lies a sport of extraordinary depth, where strategy, nerve, and precision combine to produce some of the most compelling competition in world sport. Understanding these rules is the first step to appreciating what makes professional darts so thrilling to watch and so rewarding to play.