Basic structure
- A game has 10 frames.
- In frames 1–9 you get up to two rolls to knock down 10 pins. In the 10th frame you can get up to three rolls depending on strikes/spares.
Symbols commonly used
- X = strike (all 10 pins on first roll).
- / = spare (all remaining pins on second roll).
-
- = miss (0 pins).
- A number = pins knocked down that roll.
Scoring rules
- Open frame (no strike or spare): score = pins knocked down in that frame (sum of two rolls).
- Spare: score = 10 + pins knocked down on the next single roll.
- Strike: score = 10 + pins knocked down on the next two rolls.
- The score for a frame includes its bonus (if any) and is added cumulatively.
Tenth frame special case
- If you roll a spare in the 10th, you get one extra bonus roll to determine the spare bonus.
- If you roll a strike in the 10th, you get two extra rolls to determine the strike bonus.
- Those extra rolls only count as bonuses for the 10th frame; there is no 11th frame.
Examples
- Open frames: frame 1 = 7 and 2 → frame score = 9.
- Spare: frame 1 = 7 and / → frame score = 10 + next roll. If next roll is 4, frame 1 = 14.
- Strike: frame 1 = X → frame score = 10 + next two rolls. If next two rolls are 7 and 2, frame 1 = 19.
- Perfect game: 12 strikes (X in frames 1–9, then X,X,X in 10th) → 300 (each of first 9 frames = 30, 10th = 30).
- Example partial scoring:
- Frame 1: X (strike)
- Frame 2: 7, / (spare)
- Frame 3: 4, 2
Scores: - Frame 1 = 10 + next two rolls (7 + 3) = 20
- Frame 2 = 10 + next roll (4) = 14, cumulative = 34
- Frame 3 = 4 + 2 = 6, cumulative = 40