21 checkout
In short
21 checks out in two darts under double out: S5, D8, for 5 + 16. If the double 8 lands in the single 8, 8 is left and still on: D4. And if the double 4 drops into the single 4 as well, 4 is left for the next visit: D2. With a single dart in hand, S5 leaves 16, so D8. Under straight out, where any segment can finish: T7. Under master out, where a treble can finish: T7.
S5
5
D8
16
When a dart strays
A missed treble or double often drops into the single of the same segment, and a missed bull into the 25 around it. Here is what that leaves, and what comes next.
double 8 → single 8
8 left, with the last dart
D4
8
With fewer darts in hand
The finish is then out of reach: these darts set up the next visit.
One dart
leaves 16, so D8
S5
5
Under the other checkout rules
Master out
finish on a double or a treble
T7
21
Straight out
any segment can finish
T7
21
Neighbouring scores
Let DartSync work out your finish
In a game, the scoreboard shows the route every visit, following the checkout rule you chose.
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