301 Tournaments
301 is the most popular rule variation in darts tournaments, and the rules are the easiest to understand. Each player begins with a score of 301. Each target that is hit will subtract the corresponding amount from the player's total score. For example, if a player records three 20s in his first three darts, he will have 60 points subtracted from 301. His next three darts will then be subtracted from 241. To win the game, a player must reduce his score to exactly zero. The winner then advances to the next round where they will play the winner of another match. The last man standing is crowned the winner of the tournament.
At the start of the game --- as with all games of darts --- each player throws one dart aimed at the bull's-eye. The player who is closer begins the game.
Other variations of 301 exist, such as 401, 501 or even 1,001; however, the standard variation in tournaments is 301, partly due to the amount of time needed to finish the others.
Cricket Tournaments
Cricket is the second most common variety of darts played in tournaments; however it is often considered to be the most played variation by amateurs and professionals alike. The rules are slightly more complicated than 301; however, cricket provides more variation than simply hitting 20s. Cricket requires players to hit specific targets on the board three times, from 15 to 20. For example, one player hits two 20s and one 3. He will now score two 20s (leaving one remaining) but no score is recorded for hitting the 3. Once the player has recorded three 20s, it is considered "closed." Once a player has closed the 15s, 16s, 17s, 18s, 19s and 20s, the player must now shoot three bull's-eyes. The outer circle is scored as one bull's-eye, while the inner circle is considered two. The player who closes all targets first is crowned the winner.
Other variations exist. The most notable is points cricket. Instead of simply "closing out" a number, a player can record points if a target is "closed" and his opponent has a target open. For example, a player has closed 20s while his opponent has only hit one. Every time he hits a 20 he will be able to record 20 points for himself. He can continue to do so until his opponent closes the 20s.
Around the Clock Tournament
Around the Clock is a commonly played rule set for amateur pub darts games due to the simplicity of the game; however, it is rarely played in tournaments. The rules are simple: hit each number on the dart board in numerical order. That means a player must hit the one target, followed by two and so forth. The player who completes all 20 targets is crowned the winner.