Fabric Yardage Calculator

Twenty-four squares cut 5 × 5 in from 42 in fabric need 1/2 yard. Enter your pattern’s cut sizes, seam allowance included (never the finished size), and how many of each; the calculator rounds the total up to the next 1/8 yard. WOF (width of fabric) runs selvage to selvage; selvages are the factory edges you trim off.

How the fabric yardage calculator works out your yardage

Quilters sew a 1/4 in seam, so by our arithmetic a 5 in cut square finishes at 4 1/2 in.

1. Pieces per strip: usable width (less any shrinkage) ÷ piece width, rounded down. 42 ÷ 5 = 8.4, so 8 squares fit across.
2. Strips: pieces ÷ pieces per strip, rounded up. 24 ÷ 8 = 3 strips.
3. Length: strips × piece height, added up for every height. 3 × 5 = 15 in.
4. Yardage: length ÷ (1 − shrinkage) ÷ 36, plus any margin in yards, rounded up to the next 1/8 yard. Shrinkage and margin are both optional. Here, 15 ÷ 36 = 0.417 yd, so 1/2 yd.

The “Show the math” panel lists these lines; load this example to compare (it replaces your list). The steps are exact for one piece size, unless the calculator turns that piece or it’s a full-width strip (see the FAQs). With mixed widths of one height, the calculator shares strips, so its total can come in shorter than a hand count.

Pre-wash shrinkage and a margin for mistakes

“Cotton fabric shrinks - between 3% and 5%,” says a post on fabric maker Moda’s blog, and “Fabric shrinks primarily in the width”. It adds: “For most of us, pre-washing is a personal choice.”

The calculator applies the percentage to the length as well as the width; counting the length too is its cautious assumption. At 5%, the usable width drops to 39.9 in, only 7 squares fit, and you need 4 strips (20 in cut, or 21.05 in with the shrinkage allowance), or 5/8 yd (load this example). Shrinkage costs a whole strip when a piece barely fits.

C&T Publishing’s backing calculation adds “an extra 1/8-1/4 yard to the yardage calculation to allow for crooked cuts off the bolt.” An extra 1/8 yd takes the example to 5/8 yd (load this example).

Our advice: if you’ll pre-wash before cutting, keep the 42 in width and enter a percentage. That counts some width loss twice (see below), which errs toward enough. Leave it at 0 if you won’t pre-wash or measured the width after washing. If the fabric will be hard to match, add a margin for your own miscuts too.

What width of fabric to enter

Enter 42 in unless you’ve measured your fabric. Defaults differ:

• 44 in: quilting cotton as usually sold (Fat Quarter Shop), but “not all 44″ is usable, as some fabric companies have wide selvages” (Polka Dot Chair).
• 43 in: the default at Quilter’s Paradise.
• 42 in: our assumption: 44 to 45 in, less the selvages and some shrinkage.
• 40 in: C&T Publishing, which says it “conservatively describes quilting fabrics”.

In a Sewing Street guide, Emma Bradford works through 108 squares of 4 1/2 in at 40 in: 14 strips, 63 in. The calculator agrees: 1 3/4 yd (load this example). At 42 in, 9 fit per strip instead of 8, so 12 strips make 54 in, or 1 1/2 yd (load this example).

Our advice: trim the selvages, measure yours and enter that width. Buying before you can measure? 40 in is the safer guess.

When the calculator turns a piece on its side

To save fabric, the calculator may turn a piece; if grain or print direction matters, check the note under the result, which names it. Crosswise grain runs selvage to selvage and, per Polka Dot Chair, “has a bit more stretch than the lengthwise grain,” which runs parallel to the selvage.

Take 3 pieces 4 in wide × 20 in high. Upright, they fill one 20 in strip: 5/8 yd. Turned, two fit across each 4 in strip, so 2 strips make 8 in, or 1/4 yd (load this example).

Our advice: nothing keeps a piece upright, so for a directional print or a piece you want on the lengthwise grain, work its strips by hand with the four steps.

Cutting the strips safely

Cut each strip across the WOF with a rotary cutter and ruler, then sub-cut it. Rotary cutter maker OLFA says: “Cut away from yourself, never toward yourself.” Keep your hand on the ruler “with fingers away from the edge,” and “Automatically close the cutter when you complete a cut.”

Sizing the whole quilt

Planning more than the top? The quilt size chart sets the finished size and carries it into the backing and binding calculators, so you enter it once. Enter the top’s pieces here, from your pattern’s cut list or your own block math.

FAQs

How do I calculate how many yards of fabric I need?

Work out how many pieces fit across each strip and how many strips that takes. Then add up the strip heights and round up to the next 1/8 yard. The four steps above walk through it with numbers.

How many 5-inch squares can you cut from a yard of fabric?

56, at 42 in usable width. A yard is 36 in, which holds 7 strips of 5 in, with 8 squares across each. The 57th square needs an eighth strip: 40 in, or 1 1/8 yd. Below 40 in usable, fewer fit per strip, and a shrinkage percentage can lower the count too.

How do I enter strips cut × WOF, or a long border?

Enter a strip cut across the WOF as your usable width by the strip height, such as 42 × 2 1/2 in, or, for straight-grain binding, use the binding calculator’s button that adds its strips here. The calculator treats any piece with a side within 1 in of the usable width you entered as a full-width strip: one per strip, cut crosswise and never turned, so strips can share a list and a shrinkage setting with your other pieces. Shrinkage only lengthens the cut, since a crosswise strip spans whatever width the washed fabric has. The 60 × 72 example’s 7 binding strips from the binding calculator need 17.5 in, or 1/2 yd, and at 5% they need 18.42 in, or 5/8 yd. A piece that fits your fabric but not its shrunk width, such as 40 1/2 in at 5%, also stays crosswise, with a warning to pre-wash and measure before cutting.

A piece longer than the usable width, such as a 60 × 4 in border, is cut lengthwise, along the selvage, and the result says so; two of those borders take 1 3/4 yd. To piece a border from crosswise strips instead, enter it as shorter lengths. Only a piece wider than the fabric either way is rejected.

Is a yard of fabric 3 feet by 3 feet?

No. A yard is 36 in long by the width of the bolt; see what width of fabric to enter.

How much does quilting cotton shrink, and should I pre-wash?

Between 3% and 5%, mostly in the width, according to a post on Moda’s blog, which adds: “For most of us, pre-washing is a personal choice.” (Details above.) The same post says pre-washing extra-wide backings (wide backs, the extra-wide fabric made for a seamless quilt back) is recommended. That matters if you’re using the backing calculator.

Can I cut these pieces from fat quarters?

A fat quarter is a precut piece measuring 18 × 21 in, according to Fat Quarter Shop, a quilt retailer. This calculator plans cuts from yardage across the full WOF, so it doesn’t count fat quarters. By our arithmetic, 5 in squares fit 3 across the 18 in side and 4 down the 21 in side, so 12 per fat quarter. The 24 squares need 2 fat quarters, the same amount of fabric as the 1/2 yd answer: two 18 × 21 in pieces make an 18 × 42 in half yard. For other sizes, see what you can cut from a fat quarter.