X01 rules: 501, 301 and finishing on a double
X01 is the game everything else in darts is measured against. Both players start on the same number — 501 in a tournament, 301 in a hurry — and throw three darts a visit until one of them lands on exactly zero.
How it works
Everybody starts on the same score. 501 is the standard singles game, 301 the short one, and 701 or 1001 exist for an evening with nowhere to be. This board will also take any start score you type.
You throw three darts, the total comes off your remaining score, and the next player throws. That is a visit. A game of X01 is a leg, and a match is a race to a number of legs.
The first player to reduce their score to exactly zero wins the leg. Not below it, not to one: exactly zero, on a dart that satisfies the out rule below.
Scoring the board
Each of the twenty numbers scores its face value in the big single beds, double in the thin outer ring, treble in the thin inner ring. The outer bull is 25 and the inner bull is 50.
The treble twenty is 60, which makes 180 the maximum visit and the reason everyone throws at that corner of the board. A ton is 100, a ton-forty is 140.
Busting
A visit that would take you below zero, to exactly one, or to zero on a dart that is not a legal finish is a bust. Your score goes back to what it was at the start of the visit and your throw is over — the darts already scored that visit are wiped with it.
That is why the leave matters as much as the score. Throwing 501 down to 1 is a bust from which the whole visit is lost; throwing it down to 40 is a dart at double top.
Wiping the whole visit is the tournament rule, and it is not the only one played. Which of the two this board plays is a house rule, and it is a question only per-dart scoring can answer: a three-dart total cannot say which dart busted, so a board typing visit totals plays the classic rule whatever the card says.
Each is the whole of what it does. Visit wiped — a bust wipes the whole visit — the score goes back to what it was when the player stepped up, which is the tournament rule and what televised darts plays. Darts before it stand — a bust ends the visit and nothing else — the darts thrown before the busting one keep their score, the way plenty of pubs play it, so a 20 and then a treble off 40 leaves 20 rather than 40.
In and out
Double out is the rule every tournament plays and the one this board defaults to: the dart that takes you to zero has to land in a double. The inner bull counts as the double of 25, so 50 is a legal finish.
Straight out ends the leg on any bed, which is how most pubs actually play. Master out takes a double or a treble.
Bull out is the league and pub rule the free scoreboards leave out: the dart that takes you to zero has to be the 50 itself. That moves the floor as well as the finish — a visit leaving you under 50 busts, so 30 left is a lost visit rather than a leave — and it puts two more scores, 156 and 153, on the bogey list. Bull-25 out is the kinder house version: the outer ring finishes too, which puts 25 to 49 back in range. Both are scored here, and both have their own chart — every bull-out finish, 170 to 50. Set it up →
The same three rules exist at the other end. Straight in — the default — lets you start scoring immediately; double in means nothing counts until a dart lands in a double; master in takes a double or a treble to open.
Checkouts and bogey numbers
From 170 down, most scores can be taken out in three darts, and the famous one is 170: T20, T20, Bull — the biggest possible finish. The board calls a route out for you unless you turn the hints off.
Seven scores under 170 cannot be finished in three darts at all, no matter how they are thrown. They are the bogey numbers: 169, 168, 166, 165, 163, 162 and 159. Leaving yourself on one of them means throwing a setup dart and coming back next visit.
Every route from 170 down to 2 is on the printable checkout chart, taken straight out of the module the scoreboard calls them from.
Legs, sets and the throw
A match is a race: first to three legs, first to five, whatever the pair of you agree. Sets nest that — first to three legs takes a set, first to three sets takes the match — which is how the televised game is played.
The throw alternates leg by leg, so whoever throws first in leg one throws second in leg two. Holding your own throw is a hold; taking the other player’s is a break.
Who throws first is worth more than it looks: on a 501 leg the player who leads is a visit ahead all the way down, and three of them in a row is most of a match. Televised darts rotates the throw and this board defaults to that — but almost nobody at a pub board does, and the two rules everybody actually plays are house rules here.
Each is the whole of what it does. Rotate — the throw rotates seat by seat, leg by leg — whoever throws first in leg one throws second in leg two, however the leg went. Loser throws — whoever lost the leg throws first in the next one, the way the pub plays it — with three or more players the seat after the winner leads, so winning a leg always costs the throw. Winner throws — whoever won the leg stays on the oche and throws first again, the way an exhibition is played — the throw has to be taken off them.
A bull-off, if one is thrown, still decides the leg it was thrown for; the rule owns every leg after it. Hold and break are counted against whoever actually opened the leg either way, so the numbers stay true under all three.
House rules this board plays
The part no other rules page has, because no other site implements them. Each one opens the setup screen with that rule already set.
- Per-dart entry Enter each dart as a bed rather than typing the three-dart total, and the board keeps a real checkout percentage and a dart-by-dart record of the leg. Set it up →
- Double in, double out The strict 301 of the old league card: nothing counts until a double lands, and nothing finishes without one. Set it up →
- Sets, and a two-clear-leg decider Best of five sets, and a set that reaches 2–2 has to be won by two clear legs — with a hard cap so an advantage set cannot run all night. Set it up →
- Work your own out-shot No suggested route, no "you require" call. The cheapest handicap on the board, and the only way anybody ever learns the finishes. Set it up →
- The loser throws first The rule every pub in the country plays, and the one televised darts does not: losing the leg buys the throw back, so a 2–0 is not the hole the rotation makes it and a comeback starts with an advantage rather than against one. Set it up →
- Bull out Only the 50 finishes. The biggest out is still 170, thrown T20 T20 Bull, but nothing you have practised on the doubles ends a leg and the score to sit on is 50. Set it up →
- The darts before the bust stand A bust ends the visit and nothing else: everything thrown before the busting dart keeps its score, so 40 left, a 20 and then a treble leaves 20 rather than 40. Scored dart by dart, because a three-dart total cannot say which dart busted. Set it up →
- A restriction instead of a head start Every other handicap hands the weaker player something — a start score, legs in the race, the checkout hints taken away. This one takes beds off the stronger player instead. Doubles only: only the double ring scores — a single or a treble is thrown, counted and worth nothing, and the bull pays only its 50. No trebles: the treble ring scores nothing at all — the 60 everybody leans on is gone and a big visit has to be built out of singles and doubles. Or no treble 20: the one bed a strong player lives in scores nothing — every other treble still pays, so the 19s and the 18s are the way round it. Set per player on the roster, and scored dart by dart, because a three-dart total cannot say which bed a dart hit. Set it up →
- A start score off the band Rather than playing the number on the card, deal the start score at random inside a band — so nobody arrives with a leg already memorised. Set it up →
Common questions
- What score do you start on in 501? Both players start on 501 and throw three darts a visit until one of them lands on exactly zero. 301 is the short game, 701 and 1001 are the long ones, and this board will take any start score you type.
- Do you have to finish on a double? In double out, which every tournament plays and this board defaults to, the dart that takes you to zero has to land in a double, and the inner bull counts as the double of 25. Straight out ends the leg on any bed, master out takes a double or a treble, and bull out takes the 50 and nothing else.
- What are the bogey numbers in darts? The seven scores under 170 that cannot be finished in three darts however they are thrown: 169, 168, 166, 165, 163, 162 and 159. Leaving yourself on one means a setup dart and coming back next visit.
Play it
X01 is one of the twenty modes in Friendly Fire Casper, a free darts scoreboard that runs in a browser and keeps working when the wifi drops. It scores the game for you, undoes the dart you typed wrong, remembers who won, and can put the board on a TV while everybody scores from their own phone.