The arithmetic at the oche is not the subtraction
Everybody can take 60 off 180. What people get wrong is what is left, because a leg has to finish on a double. 32 is a good number. 33 is not. And there are scores you cannot finish from at all in three darts, however well you throw.
The bogey numbers
159, 162, 163, 165, 166, 168, 169.
Every one of them is a dead end in three darts. Nothing about them looks any different from the numbers on either side, which is what makes leaving yourself on one both easy and infuriating. The highest score you can finish from is 170: treble 20, treble 20, bullseye.
Those seven are not typed in here. They come out of searching every combination of up to three darts that ends on a double, and the tests assert the search produces exactly that list. If the arithmetic were wrong the tests would fail, rather than quietly agreeing with a chart somebody copied off a poster.
The bull is a double, and people forget
It is the double of the outer bull, which scores 25. So 50 finishes a leg and 25 does not, and a checkout of 100 can be treble 20 then the bull rather than needing a specific double.
It is the rule that catches people working a finish out in their head, usually at the point where they have left themselves on something awkward and are trying to talk their way out of it.
A running total, not a list of numbers
The reason darts scores are written in two columns, with what is scored on one side and what is left on the other, is that nobody wants to add fifteen numbers up at the end and find two people disagree.
Kept as you go, the total is right or wrong immediately, so a mistake is caught on the next throw instead of at the end of the leg when nobody can remember what anybody scored. Every sheet here is ruled for that, whichever game it is set to.
How many columns fit?
Twelve players will go on an A4 sheet and you will not enjoy writing on it. Past about eight, each column is narrow enough that the figures get cramped, and a hurried 7 starts looking like a 1 in a way that causes an argument two legs later.
Two sheets is easier than one crowded one. It also means two people can score at the same time, which is how a league night actually runs when there are two boards going.
The other games
Cards gives a column for the hand and a column for the running total, which is what whist, crib and most trick-taking games need. Rounds gives a round number against a score, for a quiz or a tournament. Tally is a single column for anything you are simply counting.
All of them are ruled rather than blank, because the whole value of a printed score sheet over a piece of paper is that the numbers land in a line and can be added down a column.
Everything is generated on your own machine. Nothing is uploaded and there is no account.
Common questions
What are the bogey numbers in darts?
159, 162, 163, 165, 166, 168 and 169. You cannot finish from any of them in three darts, because you have to end on a double and no combination gets there. Nothing about them looks different from the numbers either side, which is what makes leaving yourself on one the classic mistake.
What is the highest checkout?
170: treble 20, treble 20, bullseye. Anything above that needs a fourth dart. The table on the second page starts at 170 and works down.
Why does the bullseye count as a double?
Because it is the double of the outer bull, which scores 25. That is why 50 can finish a leg and 25 cannot, and why a checkout of 100 can be treble 20 then the bull rather than needing a particular double.
Are the checkouts copied from a chart?
No, they are worked out from the board itself: every single, double and treble plus both bulls, searched for the shortest finish that ends on a double. The tests check that every line adds up to the score it claims and ends on a double, so the table cannot be wrong in the way a typed one quietly is.
Why start at 501?
It is the standard for singles and doubles darts. 301 is quicker and is usually played straight in and straight out. Anything else is a house rule, which is fine as long as everybody agrees before the first throw rather than after it.
How many players fit on a sheet?
Up to twelve, though past about eight the columns get narrow enough that the numbers are cramped and a scrawled 7 starts looking like a 1. Two sheets is genuinely easier to write on than one crowded one, and it lets two people score at once.
Can I use it for something other than darts?
Yes. Cards gives a hand column and a running total, rounds gives a round number and a score, and tally gives a single column for anything you are simply counting. The checkout table is darts only, for obvious reasons.
Why keep a running total instead of adding up at the end?
Because a running total is right or wrong immediately, so a mistake is caught on the next throw. Add fifteen numbers up at the end and two people will get different answers with no way of working out who is wrong.