Darts is one of the easiest sports to follow once you know one idea: the score counts down, not up. Every player starts a leg at 501 points, and each dart thrown subtracts from that total. The first player to reach exactly zero wins the leg — but only if the last dart lands in a double. This guide explains the board, the counting, and the finishes that decide matches.

The board: what each section is worth

A dartboard has twenty numbered segments, from 1 to 20, arranged in a fixed order around the board. The numbers are not in sequence: 20 sits at the top, with 1 and 5 beside it, and the rest follow a pattern designed to punish misses. A dart in a plain segment scores that segment's number.

Two thin rings change the value. The outer ring doubles the segment: a dart in double 20 scores 40. The inner ring trebles it: treble 20 scores 60, the highest score possible with a single dart. The centre has two parts: the outer bull scores 25, and the inner bull scores 50. Three darts at treble 20 give 180, the maximum score from one visit to the board.

The board hangs with its centre 1.73 metres above the floor, and players throw from behind a line 2.37 metres from the board. Those two measurements are fixed wherever the game is played.

Counting down from 501

Each player starts at 501. On a turn, called a visit, a player throws three darts, and the total scored is subtracted from their remaining score. So a visit of treble 20, treble 20 and single 20 scores 140 and leaves 361. The arithmetic is part of the sport: players and crowds track the remaining score constantly, and professional players work out their finishes several visits ahead.

A leg is one race from 501 to zero. A set is a group of legs, and a match is a group of sets; the exact format varies by tournament, but the leg is always the basic unit.

Finishing on a double: the checkout

Here is the rule that decides most legs: the final dart must land in a double (or the inner bull, which counts as a double). If a player reaches exactly zero without a double, the leg is not won. If a player goes below zero, or reaches one when a double is needed, the score is bust: the visit does not count, and the player's score returns to what it was at the start of that visit.

This is why the end of a leg is a puzzle. With 40 remaining, the player aims at double 20. With 32 remaining, double 16. With 36, a single 20 leaves double 8, or the player can go straight at double 18. Players plan their visits so they arrive at a comfortable double, and the best checkouts are the ones that leave a single dart at a double rather than a fiddly combination.

Some finishes are famous because they are the highest possible. The biggest checkout is 170: treble 20, treble 20, inner bull. It is the only way to finish from 170, and crowds rise for it because there is no alternative route. Other common high checkouts are 167 (treble 20, treble 19, inner bull) and 161 (treble 20, treble 17, inner bull).

Why treble 20 dominates

Almost every professional visit starts at treble 20, and the reason is simple arithmetic: it is the highest-scoring single target. A player who hits it three times scores 180, while a player who starts at treble 19 can only reach 171. The trade-off is the neighbours: miss treble 20 slightly and you land in 1 or 5, which is why the board's number order matters. The 20 segment is deliberately flanked by low numbers, so a miss is punished.

Beginners often aim at the big 20 segment rather than the treble, accepting lower scores in exchange for consistency. That is a sensible trade: three darts in single 20 still score 60 and keep the counting simple.

Match formats and sets

A leg is won by finishing first, but matches are decided over legs and sets. In a legs match, the first player to a set number of legs wins. In a sets match, legs are grouped into sets, and the first player to a set number of sets wins. Some tournaments also use a tie-break rule in a deciding set, where a player must win by two clear legs, up to a limit. The format is announced before each tournament, and it changes tactics: a short legs race rewards fast starts, while a long sets match rewards patience.

Questions, answered

Why does the score count down? Because the game is a race from 501 to exactly zero, which makes the finish a puzzle instead of a sprint.

What happens if I go below zero? Your score is bust. The visit does not count and your score goes back to where it was before the visit.

Why must the last dart be a double? That is the rule of the standard game: a leg is only won by finishing on a double (or the inner bull, which counts as a double).

What is the highest checkout? 170, finished as treble 20, treble 20, inner bull. It is the only route from that score.

What is a 180? Three darts in treble 20, the maximum score from one visit.

What to watch next

Watch a leg and follow the counting: 501 down, visit by visit, until someone is on a finish. Once you can see the checkout puzzle, the tension of the last few darts makes sense. Head to the live scores section to see which darts matches are on today, and check the darts page for fixtures and results.