A circle skirt is cut as a ring of fabric: the inner circle fits the waist and the outer edge forms the hem. Fuller skirts (full circle) drape in deep folds; half and quarter circles use less fabric and sit flatter. For wide skirts the full circle is usually cut as two half circles because fabric is rarely wide enough.
How to use the Circle Skirt Calculator
- Skirt type
- Waist
- Skirt length
- Hem allowance
- Waist seam allowance
Results update as you type, and every field accepts the units shown in its menu.
How it works
Choose the skirt type, enter your waist, the finished length, hem allowance and seam allowance.
Tips
- Measure over thin clothing with a soft tape held snug but not tight, and keep the tape level all the way round.
- Take each measurement twice; if you are between sizes, the larger size is usually the safer choice.
- Size charts vary by brand and country – check the maker’s own chart when it is available.
- For sewing projects, pre-wash fabric before cutting and buy 10% extra for shrinkage, pattern matching and mistakes.
Common mistakes to avoid
- Mixing inches and centimetres between the tape and the size chart.
- Forgetting seam and hem allowances when cutting fabric.
- Measuring an old, stretched garment instead of your body.
Inputs explained
| Field | What to enter |
|---|---|
| Skirt type | Choose one: Full circle, Three-quarter circle, Half circle, Quarter circle |
| Waist | Units: in, cm |
| Skirt length | Units: in, cm |
| Hem allowance | Units: in, cm |
| Waist seam allowance | Units: in, cm |
What each result means
- Waist radius to cut = [Skirt type]×[Waist]÷(2×pi) – [Waist seam allowance]
- Outer (hem) radius = [Waist radius to cut] + [Skirt length] + [Hem allowance]
Example values
How the main result changes when Waist changes and everything else stays at the example values above:
| Waist (in) | Waist radius to cut (in) |
|---|---|
| 14 | 1.6 |
| 21 | 2.72 |
| 28 | 3.83 |
| 35 | 4.95 |
| 42 | 6.06 |
| 56 | 8.29 |
Formula
Waist radius r = k × waist ÷ 2π − seam allowance (k = 1 full, 4/3 for ¾, 2 half, 4 quarter)Outer radius R = r + length + hemFabric: full circle needs a square of 2R (or two half circles)Worked example
Inputs — Skirt type: Full circle; Waist: 28 in; Skirt length: 22 in; Hem allowance: 1 in; Waist seam allowance: 0.625 in.
Results — Waist radius to cut = 3.83 in; Outer (hem) radius = 26.83 in; Fabric width needed = 53.7 in; Fabric length needed = 53.7 in.
Frequently asked questions
How much fabric for a full circle skirt?
A square with sides twice the outer radius – for a 22 in skirt on a 28 in waist, about 54 × 54 in, or about 3 yards of 45 in fabric cut as two halves.
Why subtract the seam allowance from the waist radius?
So that after sewing the waistband the finished waist matches your measurement.
Do I need a zipper?
Usually yes, unless the waistband is elastic.
What formula does the Circle Skirt Calculator use?
Waist radius r = k × waist ÷ 2π − seam allowance (k = 1 full, 4/3 for ¾, 2 half, 4 quarter).