Why Does It Take 12 Strikes to Reach 300 in Bowling?

Ten Frames in Bowling—Plus Those Extra Two Shots

A strike
Gerwin Sturm/Flickr/CC BY-SA 2.0

Most people who've ever bowled know that there are 10 frames in a game of bowling. Add to that bowling's perfect score—300—and it stands to reason that 10 strikes in a row is a perfect 300. But if you do the math, you'll realize that this isn't actually the case.

You Need Two More Shots 

The tenth frame consists of at least two and possibly three shots. A strike counts as 10 plus the sum of the next two shots.

So if we had one only chance to throw a strike in the 10th frame, what happens to those next two shots? If the 10th frame was treated the same as each of the previous frames, there would be no extra two shots and the maximum score would actually be 270—30 in each of the first eight frames, 20 in the ninth because only one shot was thrown on top of that strike, totaling 260 plus 10 in the 10th frame. 

That's why we have the fill balls. These shots give bowlers a chance to complete their scores on strikes and spares in the 10th frame. If you throw a spare, you get one more shot to complete the score of the spare. If you throw a strike, you get two more shots to complete the score of the strike.

12 Strikes to 300

If you start a game with 10 strikes in a row, you're doing pretty well for yourself, but you haven't reached perfection yet. That 10th strike is only worth 10 pins until you throw two more shots. Throw two gutter balls and you'll finish with 270, but throw two strikes for a total of 12 and there's your 300.

A 900 Series

This challenge requires three perfect 300 games in a row. Jeremy Sonnenfeld achieved it in 1997. Others managed it before him, but Sonnenfeld's series of three games was the first to be recognized by the United States Bowling Congress. The USBC cited faulty lane conditions when it declined to certify the previous efforts. Can you even imagine scoring three perfect games only to have the achievement thrown out because of lane conditions? 

World Records

Twelve strikes is an awesome achievement, but a bowler by the name of Ben Ketola went one better. He pulled it off in 86.9 seconds in 2017. Of course, he had to use multiple lanes to do it, working his way right down the line. He'd score a strike then run to the ball return to set up for another one. He did it about 24 seconds faster than Tom Daugherty managed it back in 2015. Ketola holds the current world record: a perfect 300 game in 1:26.9.

Back in 2013, Hannah Diem became the youngest bowler to ever score a perfect 300 game in a certified event. She was nine years, six months and 19 days old.