The basics: ten frames
A game has ten frames. In each of the first nine frames you get up to two rolls to knock down all ten pins. In the tenth frame you can earn up to three rolls. The maximum possible score is 300 — a perfect game of twelve strikes in a row.
Open frame
If you don't knock down all ten pins in a frame, it's an open frame. You simply score the number of pins you knocked down. Roll a 6 then a 2? That frame is worth 8. No bonus.
Spare
A spare (marked with a slash, /) is knocking down all ten pins using both rolls of a frame. A spare is worth 10 plus the pins you knock down on your next single roll. So a spare isn't fully scored until you throw the first ball of the following frame.
Example: you spare in frame 4, then roll a 7 on the first ball of frame 5. Frame 4 scores 10 + 7 = 17.
Strike
A strike (marked X) is knocking down all ten pins on the first roll of a frame. A strike is worth 10 plus the pins from your next two rolls. That's why strikes are so powerful — they compound.
Example: strike in frame 4, then roll 5 and 3 in frame 5. Frame 4 scores 10 + 5 + 3 = 18.
Two strikes in a row (a 'double'): the first strike counts 10 plus the next two rolls — which includes that second strike (10) plus whatever comes after it. Three strikes in a row is a 'turkey,' and the first of them is worth the maximum 30 points (10 + 10 + 10).
The tenth frame
The tenth frame is special because there's no 'next frame' to borrow bonus rolls from — so the frame itself gives you extra rolls. If you strike or spare in the tenth, you get to complete the bonus right there:
- Strike in the tenth: you get two more rolls (so three total) to count the strike's bonus.
- Spare in the tenth: you get one more roll.
- Open tenth: just your two rolls, scored normally.
This is why a perfect game is twelve strikes, not ten: the tenth frame's strike earns two bonus strikes.
A worked example
Here's a short scoring run so you can see the compounding:
Frame 1: Strike. Frame 2: 7 then spare (/). Frame 3: 4 and 2.
Frame 1 = 10 + (7 + 3) = 20. (The strike borrows both rolls of frame 2; the spare's two balls were 7 and 3.)
Frame 2 = 10 + 4 (the next single roll) = 14. Running total after frame 2: 20 + 14 = 34.
Frame 3 = 4 + 2 = 6. Running total: 40.
Why your running total jumps
Because strikes and spares wait for future rolls, your scoreboard often pauses on a frame and then leaps forward once the bonus rolls come in. That delay is the part that throws people — it's not the scorer being slow, it's the math waiting for information it doesn't have yet.