Skirt Pattern Calculator

A 60cm long, 50° skirt, made 3cm wider in the waist to allow for darts in the back.
Here's a quick pattern calculator that tells you how to make two main arc pieces for a simple flared skirt. It does not consider seams, hems, or seam allowance, but you can figure that out on your own.

Important Stuff

The default measurements are in inches, based on a person who's about a size 10, to give you an idea. For length, 26" is a bit more than knee-length, 16" is cute and short, 10" you'd better be wearing underwear. This whole thing uses ratios so if you want to use metric values it'll work just fine.
Desired skirt length:
Measure around waist:
Degrees per piece: (amount of flare, between 0-360°, when you lay the skirt down flat)

You can play with degrees to get something that fits both you and your fabric.

Optional Stuff

This is just to make sure you've got enough flare in the skirt to make it around your wide parts. Not applicable if you are a pencil.
Measure around the widest part this skirt has to make it around (butt, hips):
How far down is this from where you measured your waist?:
Round values to the nearest:1/


Inside radius:
Outside radius:
Half pattern width:
Full pattern width:
Pattern Height:
Fabric around hips:


Use the 'results' to measure out two identical pieces. Sew the straight edges together, and you've got a skirt! You'll probably want to use a zipper, buttons or string to hold one side together so you can get in and out of it... or, if you make three pieces, you have a lovely wrap skirt. But anyway, here's how the measurements go together.

The 'degrees' you put in will determine how much flare the skirt's got. It also determines where you put the tape measure. If you put in less than 180 degrees, pin the tape measure outside the fabric like this and swing it around the inner and outer radii:

On the other hand, if you put in more than 180 degrees, the tape measure will go inside the fabric and swing around the top:

(click on either image to see full size)

The idea is that you can play with the degrees setting to get pattern that fits the fabric you have. Lovely!