• Marion Verloop

What determines the size of a bottom?

Some people find it a bit hard to understand why the diameter of a Mochila bottom is not substantially bigger when you increase more stitches each round?


A bottom with 20 rounds and 8 increases has 160 stitches in the last round. When you make the same bottom with 10 increases, you get 200 and with 12 increases you get 240 stitches. So if the bottom doesn’t get bigger where do these extra stitches go? The word math comes to mind, but that is a terrifying 😱 word for some people.

To show that there is not much difference in diameter between 8, 10 and 12 increases, I decided to crocheted 3 small bottoms.


I started with the 10 increase version and to my surprise I did not have any problems keeping the bottom flat and firm.

Then the 8 increase version. 8 increases has always been a big problem for me, it always turned into a bowl. This time I was also able to keep this bottom flat and firm, but I did get painful fingers from heavily massaging the stitches.

After a good night sleep, the bruised feeling in my fingers was gone and I was ready for the 12 increase version. 12 increases is normal for me, so I did not have any issues to keep it flat and firm.


The 8 increase bottom has 10 rounds and the 10 and 12 increase bottoms have 11 rounds.

With the 10 and 12 increase versions, you make one extra round in the beginning, so you don’t get a hole in the middle of the bottom. (You start with 5 or 6 stitches in the magic circle and then increase to 10 or 12.)


The diameters of the test bottoms are:

8 increases, 8,4 cm / 3.3 inch

10 increases, 9,1 cm / 3.6 inch

12 increases, 9,5 cm / 3.7 inch


There is a 0,7 cm difference between the 8 and the 10 increases version, but that is mainly because the 10 increase version has one extra round.

There is only 0,4 cm difference between 10 and 12 increases.

When you continue and make full size bottoms, the difference in size will stay the same.


Looking at these bottoms, it is clear that increasing more stitches each round does not make the bottom bigger. So where do these extra stitches go?

When you increase more stitches each round, the stitches come closer together and that is the reason that the diameter does not get substantially bigger.


With the 8 increase version I had 6 stitches in 2 cm.

With the 10 increase version I had 7 stitches in 2 cm.

With the 12 increase version I had 8 stitches in 2 cm.



When you want to know the size of a bottom, always look at the number of rounds. The number of rounds and the hight of the stitches determine the size of a bottom.


Now lets stop talking about numbers and go back to crochet 🧶 😄


Related video

323 views
Subscribe to my site

The Netherlands

©2019 by Cor Verloop.

Follow me

  • RavelrySecondaryLogo2020-Color
  • YouTube
  • Facebook Social Icon
  • Pinterest
  • Instagram Social Icon