Strike percentage and spare percentage
Two numbers tell you more about your game than your average does. Here's how to count them properly, and a calculator for yours.
Count chances, not frames
Strike % is strikes divided by the balls you threw at a full rack. That's every first ball in frames 1 to 10, plus any 10th-frame bonus ball thrown at a fresh rack. A clean game has 10 to 12 strike chances.
Spare % is spares divided by your spare chances: every time your first ball left pins standing and you threw a second ball at them. A frame you struck in isn't a spare chance, so it shouldn't count against you.
Dividing by frames instead makes a bowler who strikes a lot look like a bad spare shooter. That's the mistake many apps and score sheets make.
Example numbers are made up, for about 10 games. Replace them with yours.
Other numbers worth tracking
- Single-pin spare %: spares where only one pin was left. Good bowlers make nearly all of these, so it's the easiest place to find pins.
- Spare % without splits: splits drag the number down through no fault of your spare game. Taking them out shows how well you shoot the spares you should make.
- First-ball average: the pins your first ball knocks down on average. Higher means better carry and easier spares.
- Clean games: games with a strike or spare in every frame.
What the numbers add up to
Spares alone take you a long way. A spare in every frame with no strikes scores 170 if your first ball takes 7 pins each time, and 190 if it takes 9. Every missed spare costs at least the pins left standing plus the bonus the spare would have earned, so it's usually worth more than 10 pins.
StrikeKeeper counts all of these for you from the pins you tap, the right way, with splits and single pins broken out.