Fabric Yardage Calculator
How much to buy, from your pieces and the bolt width.
Calculate fabric yardage from your pattern piece dimensions and the bolt width, with how many fit across, the length needed and the waste.
The unusable edge, across both sides combined. About an inch on most bolts.
Fabric needed
5.00 yd
4.57 m · 2 per row, 6 rows
This assumes every piece runs the same way up. A directional print or a nap means pieces cannot be rotated to fill gaps, which usually costs an extra row. Add about 10% over the figure above for cutting error.
How the Fabric Yardage Calculator works
Yardage is a packing problem, not an area problem. Pattern pieces do not subdivide, so what decides the answer is how many fit side by side across the usable width — and the usable width is narrower than the bolt, because the selvedge cannot be cut into. Two pieces that each need 20 inches fit on a 60 inch bolt; three do not, and the third costs a whole extra row.
Also known as: fabric requirement calculator · how much fabric calculator · yardage estimator
How the number is derived
Start with the usable width, which is the bolt width less the selvedge — about an inch across both edges on most fabric, more on printed cotton where the colour bars run down the side. Divide that by your piece width and round down: that is how many pieces fit side by side in one row.
Divide the number of pieces by that row count and round up for the number of rows, then multiply by the piece length. The rounding in both directions is the whole point. Two pieces fit across a 60 inch bolt if each is 20 inches wide, and so do two if each is 29 inches; the fabric does not care that the second case wastes more.
Waste is the difference between the rectangle you buy and the area your pieces actually use. It is rarely under 15% for garment pieces, which are irregular, and can exceed 40% on a shaped piece like a circle skirt panel.
A worked example
Twelve pieces, each 30 inches long and 20 wide, on a 60 inch bolt. Usable width is 59 inches, so two fit per row — not three, because three would need 60. Twelve pieces at two per row is six rows, and six rows at 30 inches is 180 inches, or exactly five yards.
Had the pieces been 19.5 inches wide, three would have fitted per row: 58.5 inches against 59 available. Four rows instead of six, 120 inches instead of 180 — a third less fabric for half an inch of difference in the pattern piece. That sensitivity is why nesting pieces on a cutting layout is worth the time.
Where the answer misleads
The calculation assumes every piece runs the same way up and can be placed anywhere. Directional prints, one-way naps like velvet and corduroy, and fabrics with a pile all forbid rotating a piece to fill a gap, which typically costs an extra row and sometimes several.
It also assumes rectangles. Real pattern pieces are shaped, and a good cutting layout interlocks them so a sleeve head sits in the curve of a bodice armhole. That saves fabric the rectangle model cannot see, which is why the figure here is a safe upper bound rather than a target.
Buy roughly ten percent over regardless. Dye lots differ between bolts, so going back for another half yard is a real risk of a visible colour shift on anything cut later.
Frequently asked questions
How do I calculate fabric yardage?
Divide the usable width by your piece width and round down — that is how many fit per row. Divide your piece count by that, round up for the number of rows, and multiply by the piece length. Divide by 36 for yards.
Why can I not just divide the total area?
Because fabric is cut in rectangles, not poured. A piece 61 inches wide simply cannot come off a 60 inch bolt however much you buy, and area arithmetic will happily tell you it takes 1.1 yards.
How much does the selvedge cost me?
Usually about an inch across the two edges combined, sometimes more on printed cotton where the print does not run right to the edge. It matters when your piece width divides closely into the bolt width — an inch can be the difference between two per row and one.
Should I buy extra?
Ten percent is a reasonable margin for a cutting error or a directional print, and more if the fabric is one you cannot get again. Dye lots vary, so buying short and returning for more is a real risk on anything where colour matching matters.