calcs.homes
calcs.homes
Enter your waist measurement, desired skirt length, and fullness to get the waist radius, hem radius, and minimum fabric width for a circle skirt pattern.
Estimate only — fabric width assumes cutting on the fold; add seam allowance separately.
Waist radius = waist measurement ÷ (fullness × 2π) — since circumference = 2πr, a full circle (fullness 1) uses your whole waist measurement as its circumference, while a half circle (fullness 0.5) only traces half of one, so its radius has to be bigger to still fit your waist. Hem radius adds skirt length to that waist radius, and fabric width doubles the hem radius since patterns are typically cut on folded fabric.
Circle-cut skirts are drafted from a true circle instead of gathered fabric because the resulting bias-cut edge drapes into even ripples without darts or gathers at the waist. A fuller circle uses more fabric and falls into deeper folds; a half circle uses less fabric and drapes flatter — fullness is the main lever for how dramatic the flare looks.
A full circle skirt uses the entire 360° of a circle for maximum fullness and flare. A half circle uses 180°, giving less fullness but requiring less fabric and a smaller waist radius adjustment.
You need fabric at least as wide as twice your hem radius if cutting a single panel on the fold — check the "fabric width needed" result above, and add extra for seam allowances and a waistband.