Fabric Yardage Calculator

Fabric is sold by length off a fixed-width bolt, so yardage is a packing problem: how many of your rectangles fit across the width, and how many rows that takes. Pieces per row = bolt width ÷ piece width (rounded down — you cannot cut a fraction of a piece), rows = quantity ÷ pieces per row (rounded up), length = rows × piece height. Convert to yards by dividing by 36.

Two things change the answer in practice. First, rotation: if the print has no direction, turning the pieces 90° can pack more per row and cut the yardage dramatically — this calculator tries both layouts and keeps the cheaper one. Directional prints (nap, one-way motifs, “this side up” trees) cannot be rotated, so the toggle locks the layout. Second, shrinkage allowance: enter the measured or pattern-specified percentage and the calculator enlarges each cut dimension by that amount before packing. Fabric response varies with fibre, finish and care cycle, so test when the finished size is critical.

A yard is 36 inches measured off the bolt — but the bolt stays full width, so the cloth you actually get depends on that width. Bolt widths vary by fabric and manufacturer, and the printed selvages are not normally part of the usable cutting area. Measure the cloth between the selvages rather than relying on the nominal bolt width; the backing examples below use 42 usable inches for a nominal 44–45-inch quilting-cotton bolt.

Pre-cuts reshape the arithmetic. A typical fat quarter is one quarter of a yard cut as an approximately 18 × 22-inch rectangle rather than a long 9-inch strip, which can suit patchwork pieces but not continuous borders or backing. Check the pack dimensions: they vary by market and manufacturer, and this calculator works from the dimensions you actually enter.

The published percentages are averages; your bolt has its own opinion. Before cutting, trim a labelled test square — for example, 8 inches — wash and dry it exactly as the finished piece will be treated, then remeasure: shrinkage = (original − washed) ÷ original × 100. An 8-inch square that comes back at 7.65 inches shrank about 4.4%. This calculator treats that number as a simple added cutting allowance, multiplying each dimension by 1.044. Exact compensation for a required post-wash size uses target ÷ (1 − 0.044), so use the exact formula or a pattern’s instructions when millimetres matter. Measure both grain directions and use the allowance appropriate to the critical dimension.

Fibre, weave, factory finish and wash temperature all change shrinkage, so a generic percentage is not a substitute for the care label or a test. If the finished piece will not be washed, leave the allowance at zero unless the pattern specifies otherwise.

A directional print locks rotation and can raise yardage on its own; a visible repeat raises it again. Matching a stripe or plaid across seams can require shifting later pieces by part or all of a repeat. This calculator does not model that alignment automatically: sketch the layout, add the needed repeat to the relevant piece dimension, and follow the pattern or supplier’s matching allowance rather than adding a universal fraction of a yard.

Borders want the opposite treatment: cutting border strips lengthwise (parallel to the selvedge) runs an unbroken print around the quilt, but lengthwise cuts demand continuous length equal to the longest border. Crosswise borders use width-of-fabric strips and may need joins, which can be visible in stripes. Model each strip as a piece, include its seam allowance, and mark the print as directional when rotation is not safe.

Many longarm workflows ask for about 4 inches per side, so these examples add 8 inches to both finished dimensions. Confirm the margin with the person or machine doing the quilting before buying. The table uses full-width panels running along the quilt length and joined on their long edges; it does not rotate the layout or include directional-print matching. A wide backing is one piece only when the required width fits its 106-inch usable span.

Suppose a tote pattern needs 12 rectangles cut 14½ × 16 inches from 42-inch quilting cotton, with a 5% pre-wash allowance. Scaled up: 15.2 × 16.8 inches. Unrotated, two pieces fit across the 42-inch width (42 ÷ 15.2 = 2.76), so 6 rows × 16.8 = 100.8 inches. Rotated, two pieces fit the other way too (42 ÷ 16.8 = 2.5), 6 rows × 15.2 = 91.2 inches — the calculator picks the rotated layout. 91.2 inches is 2.53 yards: buy 2⅝ yards.

Always enter the cut size including seam allowance — if the finished piece is 14 × 15½ with a ¼-inch seam all round, enter 14½ × 16. And if the pattern has pieces of several sizes, run the calculator once per size and add the yardages as a conservative estimate. A planned mixed-size cutting layout may use less fabric.