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Skirt Hem Calculator
Calculate new hem position and fabric for skirt length alterations.
How We Calculate This
The calculator determines whether you are shortening or lengthening, then calculates the new hem position and fabric requirements.
Shortening
Excess = Length change + Current hem - New hem depth
Lengthening
If existing hem allowance covers the change, simply re-hem. Otherwise, a facing strip is needed: Facing width = Shortfall + Hem depth + Seam allowance
Hem circumference (sweep)
A circle skirt hem is set by the waist and the length, not the hip: Hem = Waist + 2 × π × Length (the waist forms a circle of radius Waist ÷ 2π, and the hem sits one skirt-length further out). Other styles hang roughly from the hip, so their hem is approximated as a multiple of the hip measurement: Straight ≈ 1× hip, A-line ≈ 1.3× hip (about hip + 20-40 cm, per standard drafting), Pleated ≈ 1.6× hip (a typical moderate-pleat figure — knife and box pleats can reach 2-3× depending on pleat depth).
Frequently Asked Questions
You can shorten a skirt by any amount. When shortening significantly, check that darts, pockets and design details still sit correctly on the body. Very short hemlines on A-line skirts will change the overall silhouette.
Lengthening is limited by the existing hem allowance. Most skirts have 2-4cm of hem allowance. Beyond that, you can add a facing strip, decorative band, lace trim or contrast fabric panel. Old fold lines may show after pressing, so test on an inside seam first.
For straight skirts, a blind hem gives an invisible finish. A-line skirts work well with a turned and stitched hem. Circle skirts are best with a narrow rolled or overlocked hem because the curved edge cannot be turned up deeply without puckering.
Related Calculators
Trouser Hem Calculator
Calculate new hem position and fabric needed for trouser length alterations.
Hem Shortening Calculator
Calculate new hem position and fabric to remove when shortening.
Taking In Calculator
Calculate how much to take in at seams for a smaller fit.
Letting Out Calculator
Check seam allowances and calculate letting-out possibilities.
Tapering Calculator
Calculate tapering amounts for gradual seam adjustments.
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Last updated: March 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.