Circle Skirt Pattern
Waist and outer radius for a full, ¾, half or quarter circle skirt from your waist, ease, length and hem, and the fabric it takes cut in one piece or wedges.
The radius to mark at the waist (with the seam taken off), the outer radius, each wedge’s angle and cut size, and the fabric length from your fabric width — geometry only, every allowance yours.
Example: A full circle for a 28 in waist with 1 in ease, 20 in long with a 1 in hem: waist radius 4.62 in, outer 25.62 in; cut as two halves on 45 in fabric it needs 2.87 yd.
A ring,
not a rectangle.
Where the waist radius comes from, what the fraction of a circle changes, how the wedges are laid on the fabric, and what the page leaves to the fitting.
Two radii
A circle skirt is a ring. The inner edge is the waist: for a full circle its circumference is the waist plus ease, so the radius is (waist + ease) ÷ 2π. A half-circle skirt uses half a circle for the whole waist, so the circle it is cut from has twice the circumference and the radius is (waist + ease) ÷ (2π × ½); a quarter skirt four times. The outer radius is the waist radius plus the skirt length plus the hem allowance. The waist is a seam line: the page takes the seam allowance off the inner radius so the cut edge sits inside it.
Wedges on the fabric
The skirt is cut as equal wedges — one piece, two halves, four quarters, or any count up to eight. Each wedge is a sector of the outer circle; the page takes its bounding rectangle, adds the seam allowance to a wedge that has straight edges, and lays the wedges on your fabric width in rows, turning them when that is shorter. The fabric length is rows × piece height. A full circle in one piece is a square of twice the outer radius, so it only fits wide fabric; more wedges mean more seams and less fabric.
Fullness and hem
The hem edge is 2π × (waist radius + length) × the fraction — the figure shown as the hem edge — which is why a full circle takes so much more binding or hem than a quarter. A fuller skirt on the same waist hangs from a smaller radius and falls on the bias in more places; the page does not model drape, stretch or the drop a bias-cut fabric takes after hanging.
What the number does not settle
Ease and seam allowances are yours; nothing is assumed. A waist opening (zip, placket, elastic) and a waistband are not cut here. Directional prints run every way round a circle, so the layout does not distinguish nap. Inputs stay in your browser; the same anonymous usage counts as the rest of the site apply.