Bowling

Overview

Ten frames, ten pins, and a scoring system that trips up almost everybody. A perfect game is 300.

Checked against the USBC Playing Rules 2026–2027, from the United States Bowling Congress. Rule numbers below refer to it. Lane and ball specifications are in a separate USBC document and aren't covered here.

1. Equipment and lane

Ten pins stand in a triangle at the far end of the lane, with the headpin (pin 1) at the front. You bowl from behind the foul line.

2. The frame

You get two rolls per frame to knock down all ten pins.

• All ten with the first ball is a strike. The frame ends immediately.
• Clearing the rest with the second is a spare.
• Pins left standing after two balls is an open frame.

3. Scoring

An open frame scores the pins knocked down. Strikes and spares are worth ten plus what you roll next — which is why you cannot score a frame until subsequent balls are thrown.

Result	Score
Open frame	Pins knocked down
Spare	10 + your next one roll
Strike	10 + your next two rolls

Three strikes in a row — a turkey — scores 30 for the first of them, which is the maximum possible for a single frame.

Worked example

Frame	Rolls	Frame score	Running total
1	X	10 + 7 + 2 = 19	19
2	7, 2	9	28
3	8, /	10 + 10 = 20	48
4	X	...	...

Two strikes in a row is a double; the first scores 20 plus your next ball (2d).

4. The tenth frame

The tenth frame gives bonus balls so a final strike or spare can be completed:

• Roll a strike and you get two more balls.
• Roll a spare and you get one more ball.
• Roll an open frame and you are done.

A perfect game is twelve consecutive strikes — ten frames plus two bonus balls — scoring 30 per frame for 300.

5. Fouls and dead balls

A foul is any part of your body going over the foul line and touching the lane, equipment or building, during or after delivery (5a). The ball counts as a delivery, but none of its pins count. If you have another ball to come in the frame, the pins you knocked down are put back (6b).

A dead ball doesn't count at all: the pins are reset and you bowl again (8). That happens if, for example, a pin was missing from the setup, a pin was moved or knocked over before your ball reached the pins, you bowled on the wrong lane or out of turn, or the ball hit a foreign object.

Some pinfall is illegal: the ball counts but the pins don't (6b). That includes pins knocked down after the ball leaves the lane before the pins, or by a ball rebounding off the rear cushion, and pins touched by the pinsetting machine. But pins knocked down by another pin rebounding off a side partition or the rear cushion do count (6a).

6. Splits

A split is what's left after the first ball when the headpin is down and at least one pin is down between two standing pins (such as 7–10 or 3–10), or just in front of two standing pins (such as 5–6). It's usually marked with a circle (2h).

Foul detection

Centres usually use an automatic foul detector. Where there isn't one, the captains call fouls or a foul judge is appointed (5c). A foul that the detector misses still counts if it's apparent to both captains or an official (5d).

Commonly argued

• A perfect game is 300, not 120. The bonus structure compounds.
• Gutter then all ten is a spare, worth 10 plus your next roll.
• A turkey's first strike scores 30, the maximum for one frame.
• Pins knocked down after a foul do not count.
• Crossing the foul line is only a foul if you touch the lane or anything beyond it, during or after delivery.
• Pins knocked down by a rebounding pin count. A rebounding ball's don't.