Fabric Yardage Calculator for Quilters
To find how much fabric you need, work out how many pieces fit across the usable width, divide the piece count by that number to get rows, then multiply rows by piece height. Divide by 36 for yards and round up to the next eighth. Forty-eight 5 inch squares need 7/8 yard.
How the yardage is worked out
The calculator tries the piece both ways: with its width across the fabric, then turned so its height is across.
- Pieces across = floor(usable width ÷ the dimension across). If that is 0, the piece is wider than the fabric.
- Rows = ceil(quantity ÷ pieces across).
- Length (in) = rows × the other dimension × (1 + shrinkage %).
- Yards = length ÷ 36, rounded up to the next 1/8 yd. Meters = rounded yards × 0.9144, rounded up to 0.1 m.
- Tie-break: less fabric wins, then fewer rows, then the piece unrotated.
- Fat quarters: pieces per fat quarter = max(floor(21 ÷ w) × floor(18 ÷ h), floor(21 ÷ h) × floor(18 ÷ w)). Fat quarters needed = ceil(quantity ÷ pieces per fat quarter).
Enter the cut size of each piece, not the finished size after sewing.
Usable width is what is left after you trim the selvages. The fabric width presets (40 in usable for 42 to 44 in fabric, and so on) are conservative starting values; you can change them in the calculator.
Worked examples
1. Forty-eight 5 in squares
Usable width 40 in. Across = floor(40 ÷ 5) = 8, rows = ceil(48 ÷ 8) = 6, length = 6 × 5 = 30 in. That is 0.83 yd, so 7/8 yd (0.9 m). Per fat quarter: floor(21 ÷ 5) × floor(18 ÷ 5) = 4 × 3 = 12, so you need 4 fat quarters. With 3% shrinkage the length is 30.9 in, which is 0.86 yd and still 7/8 yd.
2. Twenty pieces of 3.5 × 6.5 in
Usable width 40 in. Width across: 11 across, 2 rows, 13 in = 0.36 yd, so 3/8 yd (0.4 m). Height across: 6 across, 4 rows, 14 in = 0.39 yd, so 1/2 yd. Width across wins.
Fat quarter and fat eighth conversions
| Cut | Size | Equals |
|---|---|---|
| 1 yard | 36 in × fabric width | 4 fat quarters or 8 fat eighths |
| 1/2 yard | 18 in × fabric width | 2 fat quarters |
| Fat quarter | about 18 × 21 to 22 in (45.7 × 53.3 to 55.9 cm) | 1/4 yard of area |
| Fat eighth | about 9 × 21 to 22 in (22.9 × 53.3 to 55.9 cm) | 1/8 yard of area |
The calculator uses 21 in as the safe width of a fat quarter. For counted work, the cross stitch fabric calculator checks whether a design fits a fat quarter.
Converting between fabric widths
To move a yardage from one fabric width to another, multiply by old width ÷ new width. Four yards of 45 in fabric becomes 4 × 45 ÷ 60 = 3 yards at 60 in. Use usable widths when you can, because trimming the selvages takes a few inches. Round up to the next eighth. For fixed-size pieces, use the calculator above instead.
How to calculate fabric yardage for cut pieces
- Write down the cut size of one piece and how many you need.
- Find the usable width of your fabric after trimming the selvages.
- Divide the usable width by the piece width, rounding down, to get pieces across.
- Divide the quantity by pieces across, rounding up, to get rows, then multiply by the piece height.
- Divide by 36 and round up to the next 1/8 yard.
Frequently asked questions
How do I calculate how many yards of fabric I need?
Divide the usable fabric width by the width of one piece to see how many fit across, then divide the number of pieces by that to get rows. Multiply rows by the piece height, divide by 36 to get yards, and round up to the next eighth. Forty-eight 5 inch squares need 30 inches, or 7/8 yard.
How many fat quarters in a yard?
There are four fat quarters in a yard. A fat quarter is a half yard cut in half again along the fold, which gives a piece of about 18 by 21 or 22 inches. That is why a yard and four fat quarters cover the same area even though the shapes differ. A fat eighth is about 9 by 21 or 22 inches.
How big of a quilt will 3 yards of fabric make?
Three yards of 42 to 44 inch fabric gives about 108 by 40 inches of usable fabric, around 4,300 square inches before waste. That is enough for a crib quilt top of about 36 by 52 inches with room for binding, but not a bed quilt. The backing is extra, so work it out with the backing calculator.
What size is 4 yards of fabric?
Four yards is 144 inches, or 3.66 meters, long. The width depends on the bolt: 42 to 44 inches for standard quilting cotton, 54 or 60 inches for some home-decor and apparel fabrics, and 108 inches for wide-back. So 4 yards of quilting cotton is 144 by about 44 inches, roughly 366 by 112 centimeters.
How much fabric do I need to convert 45-inch fabric to 60-inch fabric?
Multiply the yardage by the old width divided by the new width. Four yards of 45 inch fabric becomes about 3 yards at 60 inches (4 × 45 ÷ 60). Use usable widths if you can, since selvages and trimming take a few inches, and round up to the next eighth. For fixed-size pieces, run the calculator instead.
Why round fabric yardage up to 1/8 yard?
Shops usually cut fabric in eighth-yard steps, so rounding up gives a number you can actually ask for. It also leaves a small cushion for trimming, straightening the cut edge and minor shrinkage. If your fabric is likely to shrink, add a percentage in the calculator, and prewash first if you prewash your fabrics.