Cotton Fabric Yardage: Widths, Backing, and Shrinkage
Two things decide how much cotton you buy: how wide it really is, and how much of it disappears the first time you wash it. Both are easy to check and both are commonly guessed at.
The Number That Matters Is 42, Not 44
Quilting cotton is sold as 44 inch, and most of the time you get about 42 inches you can actually cut. The difference is the selvage down each edge, which is woven more tightly than the rest and often carries printing. It behaves differently, it can pucker a seam, and it comes off.
Two inches sounds trivial until a piece needs 43 inches, at which point it stops fitting and you are buying twice the length. Measure between the selvages and plan from that number.
| Type | Sold as | Roughly usable | Typical use |
|---|---|---|---|
| Quilting cotton | 44–45" | 42" | Quilts, crafts, light garments |
| Lawn and voile | 44–45" | 42–43" | Blouses, summer dresses |
| Canvas and duck | 54–60" | 52–58" | Bags, slipcovers, heavy curtains |
| Sateen | 54–58" | 52–56" | Drapery, home decor |
| Wide backing | 108" | 106" | Quilt backs, one piece |
Wide Backing Changes the Quilt Sum Completely
This is the single biggest saving available in cotton and plenty of people never hear about it. Take a quilt top of 60 by 80 inches, with 4 inches of margin on every side for the quilter to hold on to. The backing needs to be 68 by 88 inches.
On ordinary 42 inch cotton, one width is nowhere near 68 inches, so you need two lengths seamed down the middle:
- Two lengths at 88": 2 × 88 = 176 inches
- In yards: 176 ÷ 36 = 4.9, so 5 yards
- Joined width: 84" less the seam, about 83" for a 68" requirement
You bought 5 yards and threw away roughly 15 inches of width. Now do it on 108 inch wide backing. One length of 88 inches covers the whole thing, which is 88 ÷ 36 = 2.5 yards, with no seam down the back of the quilt at all.
Half the fabric, and a better finish. Wide backing usually costs more per yard, so compare the total rather than the shelf price. The quilting calculator splits top, backing and binding so you can price the two routes against each other.
Work Out Your Own Shrinkage in an Afternoon
Published shrinkage figures are averages across weaves and finishes that have nothing to do with the bolt in front of you. Measuring it takes ten minutes of actual work.
Cut a square from the end, mark two points exactly 10 inches apart in each direction, and put it through the same wash and dry you intend to use on the finished item. Measure again. If your 10 inch mark comes back at 9.6 inches, that direction lost 4 percent.
To end up with a given amount afterwards, divide by what is left. Wanting 5 yards after a 4 percent loss means 5 ÷ 0.96 = 5.21 yards, so you buy 5.25. Note that this is buying to a measurement you took, not adding a round number because it feels safer.
For background on why weave and finishing affect dimensional change, CottonWorks has an overview of shrinking and skewing. It gives textile context and does not validate this site’s calculations. The shrinkage guide covers the other fibres.
Length Usually Goes More Than Width
Cotton rarely shrinks evenly. The lengthwise yarns are held under tension on the loom and again during finishing, so they have more to release, and it is common for length to move noticeably more than width. That is why the swatch above wants marks in both directions rather than one.
It matters because length is what you are buying. Losing 4 percent down the roll on a 10 yard order is over a foot of fabric, while the same percentage across a 42 inch width is an inch and a half. Plan the length allowance properly and treat the width loss as a reason to keep a little margin on wide pieces.
A Directional Print Costs You the Right to Rotate
Plain cotton lets you turn a piece sideways to make it fit, and that freedom is worth real yardage. A print with a clear up and down takes it away. So does a stripe, a check, or a one way motif that reads as upside down when rotated.
Check it before you buy, not at the cutting table. Hold a length up and turn it. If the design has a top, every piece has to face the same way, and any layout that depended on alternating pieces to save space needs redoing. Large repeats cost more again, which the pattern repeat guide works through with numbers.