Fabric Yardage Calculator
Divide your bolt width by the piece width to see how many pieces fit in a row, divide the quantity by that to get rows, multiply rows by piece height — that is the length of fabric you need. This fabric yardage calculator runs that layout both ways, rotates the pieces when it saves fabric, and adds your shrinkage allowance before rounding up to the eighth of a yard.
Include seam allowance
Include seam allowance
Usable width, selvage removed
5–10% for pre-washed cotton
Buy
Rotate the pieces 90° — laying them 6″ across the bolt saves fabric. 6 per row × 2 rows.
▸How this was worked out
scaled piece = 4.5 × 6″ × 1.050 shrink = 4.73 × 6.3″
across the 42″ bolt: 6 pieces per row
rows = 12 ÷ 6 = 2
length = 2 × 4.73 = 9.45″ = 0.263 yd
0.263 yd → buy 0.375 yd (fabric is sold in ⅛-yd cuts).
Shopping list
- Fabric42″ bolt0.375 yd
CraftCalc · Fabric yardage cutting note
12 pieces of 4 ½″ × 6″ from 42″ fabric (rotate pieces 90°)
Buy 0.375 yd — 6 across, 2 rows
craftcalc.io — free maker calculators with the arithmetic shown
How do you calculate fabric yardage from piece size?
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: cottons lose 3–5% in a hot wash, linens up to 10%. Enter your allowance and the calculator inflates every piece before packing, so the number you buy already includes the wash.
Worked example: 12 tote-panel pieces, 42-inch cotton
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; nesting mixed sizes by hand rarely beats the simple sum by more than a few inches.
Frequently asked questions
How much extra fabric should I allow for shrinkage?
Pre-washed quilting cotton shrinks 3–5%; apparel cottons and rayons 5–8%; linen up to 10%. If you will not pre-wash, add the shrinkage percentage here so the finished piece still measures right after its first wash.
What bolt width should I enter?
Quilting cotton is 42–44″, apparel cotton and rayon 44–54″, home-decor and fleece 54–60″, upholstery and vinyl 54–72″. Measure your actual fabric if you can — usable width is the bolt width minus both selvages.
When does a directional print cost more fabric?
When rotating the pieces would have packed them more tightly. With a one-way print every piece must face the same direction, so the calculator disables the rotated layout; the yardage shown is then the true minimum.
Does this account for pattern matching and repeats?
No — matching a large repeat (stripes, plaids) can add one full repeat length per row. Add the repeat to the piece height before entering it, or buy an extra ¼–½ yard and match by eye.
Why round up to eighths of a yard?
Most fabric shops cut in ⅛-yard (4½″) increments. 2.53 yards is not buyable — 2⅝ is, and the extra few inches covers a miscut.
Formulas and standard tables are sourced in the methodology. Results are estimates — measure twice, cut once.