Circle skirts are an A-line style of skirt that has varying degrees of fullness. The only measurement needed is the waist measurement. Below, I’ve explained how to draft different types of skirts, and how to find the circumference needed to create the pattern.

Adding ease

From my experience, the best amount of ease to add to your waist measurement is 3/8″. This gives you room to sit and move, but the skirt stays where it is supposed to. At most, I would deviate from this only by 1/8″ in either direction (making the ease 1/4″-1/2″).

Finding the radius

This is the most important part of the entire process of drafting a circle skirt. The radius is how far from a certain point you are going to mark in order to draft the waistline. Once the waistline is drawn, everything else can be added.

Why is the math so hard?

The biggest source of confusion for me when drafting a circle skirt was trying to figure out the math. Fortunately, there are so many resources available, I figured out a way to bypass having to do the math altogether. Most of the tutorials I’ve seen on this subject all gave equations involving pi, which made little sense to me. They would multiply some equation by 2, then divide by 4, and I didn’t understand what I was supposed to be doing with the number I got. However, I found a workaround using an online circle calculator.

Using an online circle calculator

To be clear, I am not talking about using an online circle skirt calculator, as I’ve discussed below. The one I am referring to is for just a regular circle shape, nothing more. Any calculator that gives you the radius based on circumference would work (here is an example).

Now that you have the tool, you have to find the circumference of the circle for the waist line. For a 1/4 circle skirt, you are making a full skirt out of 1/4 of a circle. That means the measurement of your waist has to equal the circumference of the circle /4. In order to get what that circumference needs to be, simply multiply your waist measurement by 4.

The same method is used for the other skirts. A half circle skirt means your full skirt is made out of 1/2 of a circle. Multiply your measurement by 2 to get the circumference, then use the calculator to find the radius of that circle. For a 3/4 circle skirt, multiply it by 1.333. For a full circle skirt, leave your measurement as it is.

For example, my waist measurement is 32″, which becomes 32 3/8″ after adding ease. I made a 1/4 circle skirt, so I multiplied my measurement by 4. This gave me a circumference of 129.5″. The radius of a circle with this circumference is 20.61″, or 20 5/8″ (I used this calculator to find the nearest fraction). That is the number I need to draft the pattern.

Use a chart

Another alternative to figuring out the math yourself is to use a circle skirt chart. From the ones I’ve seen, they go by the full inch. This is fine, since you can adjust the length once the pattern has been drafted. Personally, I would use this only if the measurement just happened to fall on a whole number. I prefer the first method, but this will work every time.

Use a circle skirt calculator

I’ve found this to be the most challenging method. I can never tell if the seam allowance is included, and the length of fabric required is often wrong. My advice would be to skip these altogether unless you know how to work it (example here).

How to draft a circle skirt

Once you have your circle radius, all that’s left is drawing it on paper.

1. Get a large piece of drafting paper. Draw a vertical line 1″ away from the left edge, and draw a horizontal line 1″ away from the top.
2. Mark the length of the radius from one line to the other. Connect the points to create a curve.
3. Measure the curve and adjust to match waist circumference, as needed.
   1. For a 1/4 circle skirt, measurement should equal the waist measurement. A half circle skirt should equal 1/2, 3/4 circle skirt should be 1/3, and a full circle skirt should equal 1/4.
4. Mark the length of the skirt from the waist line from one line to the other. Connect the points to create a curve.
   1. If the paper is not wide enough, add extra paper to fit remaining part of pattern.
5. Add seam allowance to the waist line, side seams, and hem. Cut out pattern.

To read about how to construct the pattern once it has been drafted, see here.