How to use it
- Type each roll in order: X for a strike, / for a spare, - for a miss, or the number of pins.
- Read Frame by frame: a frame shows its score once its bonus rolls have been thrown.
- Read Score for the total so far, and Highest score still possible for the rest of the game.
How a frame is scored
A game has ten frames, and each pin knocked down is one point. An open frame scores the pins of its two rolls. A strike (all ten pins with the first roll) scores ten plus the pins of the next two rolls, which can fall in later frames. A spare (all ten pins in two rolls) scores ten plus the pins of the next roll.
In the tenth frame a strike gives two extra rolls and a spare one extra roll. Those extra rolls are pins of the tenth frame itself, and earn no further bonus. The highest score is 300, with twelve strikes in a row.
Open frame = pins of its two rolls
Strike = 10 + the next two rolls
Spare = 10 + the next roll
Tenth frame = the pins of its rolls, with the extra rolls after a strike or spareThe highest score still possible
While a game is unfinished, the calculator tries every legal way to throw the rolls still to come, and reports the best total. The rules decide which rolls are legal: a / must follow a roll that left pins standing in the same frame, and a strike can only start a frame.
The score shown for a game in progress counts only the frames that are decided, so a frame whose bonus rolls are not thrown yet adds nothing.
What the calculator does not cover
- Handicaps and league or team scoring. The calculator scores one game of ten-pin bowling.
- Rules beyond strikes, spares and the tenth frame, such as fouls. The calculator takes the pins you type as the pins knocked down.
Worked example: a game of 131
The game X 36 36 7/ 42 9- X -8 8/ X 81 has ten frames. Frame one is a strike: 10 + 3 + 6 = 19. Frame four is a spare: 10 + 4 = 14. Frame seven is a strike with a miss and an 8 after it: 10 + 0 + 8 = 18.
The running totals are 19, 28, 37, 51, 57, 66, 84, 92, 112 and 131. The tenth frame, X 8 1, scores its own pins, 19.
| Frame | Rolls | Frame score | Running total |
|---|---|---|---|
| 1 | X | 19 | 19 |
| 2 | 3 6 | 9 | 28 |
| 4 | 7 / | 14 | 51 |
| 7 | X | 18 | 84 |
| 10 | X 8 1 | 19 | 131 |
Frequently asked questions
How is a strike scored?
A strike scores ten plus the pins of the next two rolls, which may fall in later frames. A strike in frame one followed by 3 and 6 scores 19, as the Wikipedia article gives it.
What does the tenth frame allow?
A strike in the tenth frame earns two extra rolls and a spare earns one. Those extra rolls are pins of the tenth frame and earn no further bonus.
Why does a frame show no score yet?
A strike or a spare waits for its bonus rolls, so the frame cannot be scored until they are thrown. The running total stops at the first frame that is not yet decided.
What is the highest score still possible?
It is the best total the rest of the game can reach under the rules, with every roll still to come thrown as well as the rules allow. A game of twelve strikes gives 300, the highest score.
Why is a / refused after a strike?
A spare is ten pins knocked down with two rolls in one frame, so a / must follow a roll that left pins standing. After a strike the rack is full again, so the calculator refuses a / straight after it.
Can I type the rolls with spaces?
Yes. Spaces are ignored, so X 36 36 and X3636 are the same game, and letters are read in capitals.
Sources
Figures and text last checked on Tuesday, November 10, 2026.