About the Darts Checkout Calculator
This darts checkout calculator finds the best way to finish a leg. Enter the score you have left and how many darts are in your hand, and it returns a recommended checkout route — such as T20 T20 Bull for 170 or T20 D20 for 100 — along with the minimum number of darts needed and several alternative routes.
It follows standard 501 double-out rules: the final dart must land in a double or the bullseye (which counts as double 25), and you cannot leave yourself on 1. Among routes with the fewest darts it prefers big trebles for set-up shots and favourite finishing doubles such as D20, D16 and D8, which split cleanly if you hit the single. A straight-out option is included for casual and practice games.
Use it as a quick reference while practising, to learn your outs, or to settle arguments about whether a score is a bogey number. The seven three-dart bogey numbers below 170 — 169, 168, 166, 165, 163, 162 and 159 — have no double-out finish at all.
How to use the darts checkout calculator
- 1Enter the score you have left.
- 2Choose how many darts you still have in your hand this visit.
- 3Keep double out for standard 501, or choose straight out for casual games.
- 4Throw the recommended route and re-enter the new score if you miss.
Formula and method
The calculator searches every combination of one, two or three darts (singles 1–20, outer bull 25, doubles, trebles and the 50 bullseye) whose total equals your score, with the final dart restricted to a double or the bull under double-out rules. Routes with fewer darts always rank first.
Among routes with the same number of darts, it adds a preference cost: high trebles (T20, T19, T18) and singles are preferred for set-up darts, and finishing doubles are ranked D20, D16, then D18, D8, D12 and D10, because even doubles can be halved repeatedly if you hit the single. Several valid routes exist for most scores, so alternatives are listed too.
- d₁, d₂
- Set-up darts: any single, treble, double or bull
- d₃
- Finishing dart: a double (D1–D20) or the bullseye (50)
Worked examples
170 — the big fish
170 is the highest checkout and has only one route: two treble 20s (120) and the 50 bullseye, which counts as a double.
40 — double top
40 is finished with one dart in double 20. If you hit single 20, 20 is left — D10 — so it splits well.
167 with three darts
167 − 50 = 117, and the only two-dart way to make 117 is T20 + T19, so the single route is T20 T19 Bull.
169 — a bogey number
No two darts sum to 169 minus any double, so 169 cannot be finished in one visit; set up a finish instead.
Frequently asked questions
What is the highest checkout in darts?+
The highest double-out checkout is 170: treble 20, treble 20, bullseye. It is nicknamed the “big fish”.
What are the bogey numbers in darts?+
Below 170 the scores that cannot be checked out in three darts are 169, 168, 166, 165, 163, 162 and 159. Anything above 170 also needs more than one visit.
Does the bullseye count as a double?+
Yes. The inner bull scores 50 and counts as double 25, so it can be used to finish. The outer bull (25) is a single and cannot finish under double-out rules.
Why do players prefer double 16 and double 20?+
Even doubles can be halved repeatedly. Missing D16 into the single 16 leaves 16 (D8), then 8 (D4) and so on, so a player can keep shooting at doubles without having to set up again.
What happens if I go bust?+
In standard double-out play, scoring more than you need, reaching exactly zero without a double, or leaving 1 is a bust: the visit does not count and your score reverts to what it was.