Bogey numbers in darts

Why can't a bogey number be finished?

A checkout is three darts at most, and the last one must be a double or the bullseye. Two numbers set the limits: the first two darts can score at most 120 (two treble 20s), and the biggest finishing darts are double 20, worth 40, and the bullseye, worth 50.

• Up to 160, a double in the ring can do the finishing. T20, T20, double 20 makes exactly 160.
• From 161 to 170, only the bullseye is big enough, so the first two darts have to make the score minus 50: something from 111 to 120. Two darts can make just four totals in that band, 111, 114, 117 and 120, and each needs two trebles.

That is why 161, 164, 167 and 170 go out and 162, 163, 165, 166, 168 and 169 do not. The seventh bogey number, 159, misses both routes: before the bullseye it would need 109, before double 20 it would need 119, and no two darts make either. A smaller double would need more than 120 from the first two darts.

The table runs through every score from 158 to 170, with the finish the app suggests or the reason there is none.

Checkouts from 131 to 170 lists every finish in the wider band, with what a missed first treble leaves.

Why is 170 the highest checkout?

170 is T20, T20 and the bullseye: the two biggest scoring darts followed by the biggest finishing dart. Nothing above it can be checked out, even though a visit can score up to 180. You can score exactly 171, 174, 177 or 180 with three darts, but only with a treble as the last dart, and a treble does not count as a finish. Above 170 every visit is a scoring visit.

How do you avoid leaving a bogey number?

A bogey number is usually left by the last dart of a scoring visit. Say you are on 219 and your first two darts land in the single 20. You now have 179 with one dart. A treble 20 would leave 119, a finish, but a single 20, the bigger target, leaves 159, a bogey number. Aim at 19 instead and both results work: treble 19 leaves 122 and a single 19 leaves 160.

The same check works for every score where a single 20 would leave a bogey. The treble 20 still leaves a finish in each case; the table gives the highest target where the single leaves a finish too:

The pattern is easy to remember: when a single 20 would leave a bogey number, move to the 19 or the 18.

What should you do when you are left on one?

Do not throw at a finish that is not there. Use the visit to leave the easiest finish you can for next time, ideally a single double. The usual plan, and the setup the checkout calculator suggests, is two treble 20s and then a single that leaves 32 for double 16:

If both trebles land in the single 20, the same single leaves 112 in every case, and 112 is still a three-dart finish: T20, 20, D16.

Even a perfect setup means the leg takes at least one more visit, and your opponent gets a throw at their own finish in between. That extra visit is the real cost of a bogey number.