Fabric Calculator
Fabric calculator for curtains, yardage for any project, and yard/metre unit conversion.
Curtains
General yardage (piece packing)
Unit converters
How the fabric calculator works
For curtains, the calculator first works out how much fabric width you need across the track: fullness width = track width × fullness ratio. A 60" track at 2x fullness (standard for eyelet or pencil pleat curtains) needs 120" of fabric across. Dividing that by your fabric roll width and rounding up gives the number of widths (also called "drops" or "panels") you must cut and sew together — for a 54" wide fabric, 120 ÷ 54 = 2.22, rounded up to 3 widths.
The cut length of each width is your finished curtain length plus hem allowances: finished length + top hem + bottom hem. With an 84" finished length, a 4" top hem and an 8" bottom hem, cut length = 96". If you enter a pattern repeat, the cut length is rounded up to the next full multiple of the repeat so the pattern lines up at every seam.
Total yardage = number of widths × cut length, converted from inches to yards (÷ 36) and rounded up to the nearest 1/8 yard, since most fabric shops cut in eighth-yard increments. In our example: 3 widths × 96" = 288" = 8 yards exactly. The calculator also splits that total between a single curtain panel and a full pair, since a pair usually shares the total widths roughly evenly between the two sides.
The general yardage section uses simple row packing: it fits as many pieces as possible side by side across your fabric width, then stacks rows to reach your quantity. This does not account for diagonal nesting of angled or triangular pieces, which can reduce fabric use further — for those shapes, add 10-15% as a safety margin. All results round up to the nearest 1/8 yard or nearest 10 cm so you buy enough, never slightly short.
Fabric Calculator: frequently asked questions
How much fabric do I need for curtains?
Multiply your track width by the fullness ratio (usually 2x for pencil pleat or eyelet) to get the total fabric width required, then divide by your fabric roll width and round up to get the number of fabric widths (drops). Multiply that by the cut length (finished length plus hems) to get total yardage.
What fullness ratio should I use for curtains?
Eyelet curtains typically use 2x fullness, pencil pleat around 2.25x-2.5x, pinch pleat about 2.5x, and simple flat panels can use 1.5x. More fullness means fuller-looking curtains but uses more fabric.
How do I calculate fabric for a project with a pattern repeat?
Round your cut length up to the next full multiple of the pattern repeat so each fabric drop starts at the same point in the pattern, keeping the design aligned across seams.
How do I convert yards to metres for fabric?
Multiply yards by 0.9144 to get metres, or multiply metres by 1.0936 to get yards. This tool includes a quick converter for both yard/metre and inch/cm.
Should I buy extra fabric beyond the calculated amount?
Yes, it is common to add 10-20% extra for shrinkage, cutting errors and pattern matching, especially for patterned or napped fabrics. This calculator rounds up to the nearest 1/8 yard or 10 cm, but buying a little more is a safe practice.