How to Calculate Fabric Yardage: The Formula, Charts and Quilt Examples

How do you calculate fabric yardage?

Use this four-step formula for any project:

1. List every piece with its cut size, including seam allowances.
2. Work out the length of fabric those pieces use along the bolt, in inches.
3. Divide by 36 to convert inches to yards.
4. Round up to the next 1/8 yard (4 1/2 in), then add a little extra for shrinkage and straightening the cut edge.

Two terms make the rest easy. Width of fabric, or WOF, is the measurement from selvage to selvage. Quilting cotton is sold as 42 to 45 in wide, but after trimming the tightly woven selvages you can count on only about 40 in of usable width. Length of fabric is what you are buying: a 1 yard cut is 36 in long by the full width of the bolt.

Shops cut in eighths of a yard, so it helps to know the inch value of each fraction. Keep this chart by your cutting mat, or see the fuller fabric yardage chart for metric conversions.

How do you calculate fabric yardage for a quilt?

Quilt patches are cut from strips that run across the width of the fabric. That gives a reliable three-line method:

1. Pieces per strip = usable width (40 in) divided by the cut width, rounded down.
2. Strips needed = number of pieces divided by pieces per strip, rounded up.
3. Yardage = strips multiplied by the cut height, divided by 36, rounded up to the next 1/8 yard.

Worked example: a throw needs 120 squares cut at 5 in. Forty inches divided by 5 is 8 squares per strip. One hundred twenty divided by 8 is 15 strips. Fifteen strips at 5 in tall is 75 in, and 75 divided by 36 is 2.08, so buy 2 1/8 yards. The table below runs the same method for common patch sizes.

Notice how the 12 1/2 in blocks jump to 3 1/2 yards: only three fit across the bolt, so every extra block adds a third of a strip. When a pattern has several fabrics, run the method once per fabric. The quilt top yardage calculator does this for every fabric at once, and the blocks needed calculator tells you how many blocks fill a given quilt size.

Precuts skip the math entirely if the squares suit your pattern. A charm pack holds about 42 squares of 5 in, and a layer cake holds about 42 squares of 10 in, roughly 2 3/4 yards of fabric already cut. For a stack of the same background square, a white layer cake like Bella Solids White Layer Cake saves the cutting too.

How much fabric do I need for a quilt by size?

The quilt top depends on your pattern, but the backing, binding and batting depend only on the finished size. That makes them easy to chart. The figures below use our standard coverlet sizes from the quilt size chart, 4 in of extra backing on every side, and 2 1/2 in binding strips cut across 42 in cotton.

Each row has its own detailed page: see queen quilt backing, king quilt binding and throw quilt size for cutting plans and alternate overages. Your own quilt is a different size? The quilt backing calculator and quilt binding calculator run the identical formulas for any measurement.

How much bigger does quilt backing need to be?

Backing is cut larger than the quilt top on every side, because the layers shift slightly as you quilt and the edges get trimmed square afterward. Quilters finishing on a home machine typically add 2 to 4 in per side. Longarm quilters usually ask for 4 to 6 in per side so the frame clamps have something to hold; always ask your quilter before you buy.

To calculate backing yardage for pieced cotton:

1. Add twice the overage to each quilt dimension. A 90 x 95 in queen with 4 in per side needs 98 x 103 in.
2. Divide the dimension you are spanning by 40 in of usable width and round up to get panels. 103 divided by 40 is 2.6, so 3 panels.
3. Multiply panels by the other dimension, divide by 36 and round up. Three panels of 98 in is 294 in, or 8 1/4 yards.

Check both directions (seams running vertically or horizontally), because one is often shorter. For the queen, horizontal seams use 8 1/4 yards against 8 5/8 for vertical. With 108 in wide backing, a single 103 in length covers it: 2 3/4 yards, no seams. A 3 yard cut of ROC-lon 108 in Backing covers a queen with room to spare. Our how to back a quilt guide covers seams, basting and every size.

How do you calculate binding for a quilt?

Binding is a long strip that wraps the raw edge. The formula has four steps:

1. Perimeter = 2 x (width + length). A 90 x 95 in queen is 370 in around.
2. Add 10 to 12 in for mitered corners and joining the ends: 382 in.
3. Strips = that length divided by the usable length of each strip, rounded up. Each diagonal join uses about one strip width, so a 40 in strip gives about 37 1/2 in of binding. 382 divided by 37.5 is 10.2, so 11 strips.
4. Yardage = strips x strip width, divided by 36. Eleven strips at 2 1/2 in is 27 1/2 in, which rounds up to 7/8 yard.

Binding is where small yardage mistakes hurt most, because a matching fabric can sell out. Buy the full amount with your quilt fabric. The how to bind a quilt guide has the step-by-step method and a strip chart for every size.

How do you calculate fabric yardage for clothes and home decor?

Garments are harder to calculate by hand because pattern pieces are curved and nest together differently at every size. For clothes, the pattern envelope's yardage chart is always the authority. What you can calculate is the effect of fabric width: 60 in apparel fabric usually needs about a quarter less yardage than 45 in, because more pieces sit side by side across the width.

Add extra when the fabric has a one-way print, a nap (velvet, corduroy, minky) or a large plaid to match, since every piece must be cut facing the same direction. For home decor, the formula from the quilting sections works well: curtains are finished length plus hems and header, multiplied by the number of fabric widths across the window. Use the ranges below as planning figures, then check the detailed pages.

The full list of projects lives on the fabric yardage hub, and the fabric width chart shows which fabrics come in 45, 54, 60 and 108 in widths.

Should you buy extra fabric?

Yes, a little. Three things eat into exact yardage:

• Shrinkage. Cotton commonly shrinks about 3 to 5 percent in the first wash. If you prewash, a yard can lose more than an inch of length and some width.
• Straightening. Shop cuts are rarely perfectly square to the grain. Trimming the end straight can cost an inch or two.
• Mistakes. One miscut strip on a 12 1/2 in block is a third of a yard.

A common habit among quilters is to add about 10 percent, or at least 1/4 yard per fabric, to calculated yardage. For backgrounds and borders that must match, add a bit more. For a scrappy quilt where any fabric will do, buy exact.

Accurate cutting protects your yardage as much as accurate math. A long ruler such as the Creative Grids 6-1/2 x 24-1/2 cuts full-width strips in one pass, a Olfa RTY-3/DX 60mm handles several layers at once, and a large mat like the Olfa 35x70 Mat Set lets you lay out a folded length without shifting it. If you cut a lot of the same shapes, a die cutter like the AccuQuilt GO! Big cuts up to 6 layers per pass with very little waste.