Quilt Backing Calculator
Backing yardage for 42″, 60″, 108″ or 118″ fabric, plus batting and binding.
4 for a longarm quilter; 2 to 3 for quilting at home.
2.5 is standard.
The calculator works out both seam directions and shows the one that needs less fabric. Panels are joined with ½″ seams, and every figure rounds up, so you are never short.
3 panels · 9 ¾ yd
3 panels · 8 ¼ yd
Colored bands are fabric panels, dashed lines are seams, the outlined box is your quilt top.
About the Quilt Backing Calculator
How many yards of fabric you need for a quilt backing depends on three things: the size of the top, how much extra the quilter wants on each side, and how wide the fabric is. A queen backing takes 8¼ yards of regular 42″ quilting cotton but only 3¼ yards of 108″ wide back. This calculator works out both seam directions, picks the one that uses less fabric, and draws the panel layout. It also tells you which batting package fits and how much binding fabric to cut. Pick a preset from crib to king or type your own size.
How many yards of fabric for a queen quilt backing?
8¼ yards of 42″ quilting cotton, or 3¼ yards of 108″ wide backing. That assumes a 90″ × 108″ queen top and 4″ of extra backing on every side, the usual request from longarm quilters. The backing then has to measure 98″ × 116″. Regular cotton is only about 40″ wide once the selvages are trimmed, so it takes three panels joined together. A 108″ wide back covers 98″ in one piece.
If you quilt at home and only need 3″ per side, the queen drops to 8 yards of 42″ fabric. The 108″ figure stays at 3¼ yards.
Backing yardage by quilt size and fabric width
All figures use 4″ extra per side, ½″ seams between panels and yardage rounded up to the nearest ¼ yard. Usable widths are 40″ for 42–44″ cotton, 58″ for 60″ fabric, 104″ for 108″ wide back and 114″ for 118″ wide back. The seam direction shown is the cheaper one.
| Quilt top | Size (in) | Backing (in) | 42–44″ cotton | 60″ fabric | 108″ wide | 118″ wide |
|---|---|---|---|---|---|---|
| Crib | 36 × 52 | 44 × 60 | 2½ yd (2 panels, horizontal) | 1¾ yd (no seam) | 1¼ yd | 1¼ yd |
| Baby | 40 × 40 | 48 × 48 | 2¾ yd (2 panels) | 1½ yd (no seam) | 1½ yd | 1½ yd |
| Lap | 50 × 65 | 58 × 73 | 3¼ yd (2 panels, horizontal) | 2¼ yd (no seam) | 1¾ yd | 1¾ yd |
| Throw | 60 × 70 | 68 × 78 | 4 yd (2 panels, horizontal) | 4 yd (2 panels, horizontal) | 2 yd | 2 yd |
| Twin | 70 × 90 | 78 × 98 | 5½ yd (2 panels, vertical) | 4½ yd (2 panels, horizontal) | 2¼ yd | 2¼ yd |
| Full | 84 × 90 | 92 × 98 | 7¾ yd (3 panels, horizontal) | 5¼ yd (2 panels, horizontal) | 2¾ yd | 2¾ yd |
| Queen | 90 × 108 | 98 × 116 | 8¼ yd (3 panels, horizontal) | 6½ yd (2 panels, vertical) | 3¼ yd | 3¼ yd |
| King | 108 × 108 | 116 × 116 | 9¾ yd (3 panels) | 9¾ yd (3 panels) | 6½ yd (2 panels) | 6½ yd (2 panels) |
The king row is the one that surprises people. A 116″ backing is wider than 108″ or even 118″ fabric once you allow for selvages and shrinkage, so you need two lengths. Ask your quilter whether 3″ per side is enough: at 114″ square, a single length of 118″ wide back works and the king needs only 3¼ yards.
Vertical or horizontal seams: why the direction matters
With vertical seams the panels run from the top of the quilt to the bottom. You need enough panels to cover the backing width, and each one is as long as the backing. With horizontal seams the panels run side to side, so you cover the length instead and each panel is as long as the backing is wide.
The formula is the same both ways: panels = backing side ÷ usable width, rounded up, allowing 1″ for every ½″ seam. Yardage = panels × panel length ÷ 36, rounded up. Because a quilt is usually longer than it is wide, horizontal seams often need shorter cuts, but not always. The twin is a good counter-example: two 98″ vertical panels (5½ yd) beat three 78″ horizontal ones (6½ yd). That is why the calculator runs both and shows the diagram.
Worked example: queen backing from 42″ cotton
- Top: 90″ × 108″. Add 4″ per side: backing 98″ × 116″.
- Vertical seams: two 40″ panels joined make only 79″, so you need 3 panels, each 116″ long. 3 × 116 = 348″ ÷ 36 = 9.67, so 9¾ yd.
- Horizontal seams: three panels cover 3 × 40 − 2 = 118″ of length, enough for 116″. Each is 98″ long. 3 × 98 = 294″ ÷ 36 = 8.17, so 8¼ yd.
- Buy 8¼ yards, cut it into three 98″ pieces and sew them along the long edges. You save 1½ yards compared with vertical seams.
Batting size chart
Batting should also be larger than the top: 2″ to 4″ per side, or 4″ to 8″ in total. The table uses 4″ per side and the common package sizes crib 45 × 60, throw 60 × 60, twin 72 × 90, full 81 × 96, queen 90 × 108 and king 120 × 120. Brands vary by a few inches, so check the label.
| Quilt top | Batting needed (in) | Package that fits | Binding length | 2½″ strips | Binding fabric |
|---|---|---|---|---|---|
| Crib 36 × 52 | 44 × 60 | Crib | 186″ | 5 | ⅜ yd |
| Baby 40 × 40 | 48 × 48 | Throw | 170″ | 5 | ⅜ yd |
| Lap 50 × 65 | 58 × 73 | Twin | 240″ | 6 | ½ yd |
| Throw 60 × 70 | 68 × 78 | Twin | 270″ | 7 | ½ yd |
| Twin 70 × 90 | 78 × 98 | Queen | 330″ | 9 | ⅝ yd |
| Full 84 × 90 | 92 × 98 | King | 358″ | 9 | ⅝ yd |
| Queen 90 × 108 | 98 × 116 | King | 406″ | 11 | ⅞ yd |
| King 108 × 108 | 116 × 116 | King | 442″ | 12 | ⅞ yd |
Note that a queen batting package is the same size as a queen top, so it only works for queen quilts of about 86″ × 104″ or smaller. For a full-size queen, buy a king package or batting off the roll.
Binding yardage
Binding length is the perimeter of the top plus 10″ for joining the ends and turning corners. Cut strips 2½″ wide across the width of fabric and count 40″ of usable length per strip after the diagonal joins. Strips × 2½″ ÷ 36, rounded up to ⅛ yard, is the fabric to buy. Plan to buy binding fabric separately: once the backing panels are trimmed, the leftovers are usually only a few inches wide.
Assumptions behind the numbers
- Extra per side defaults to 4″ for longarm quilting. Some quilters ask for 6″; use the field to match their request.
- Usable width allows for trimmed selvages and some shrinkage. If you prewash, measure after washing and enter that as a custom width.
- Every result rounds up, so a small amount is left over. Add a little more if the print is directional or needs matching across seams.
How to use the Quilt Backing Calculator
- 01Tap a quilt top preset (crib 36×52 up to king 108×108) or type the finished width and length of your top in inches.
- 02Set the extra fabric per side: 4″ if a longarm quilter will finish it, 2 to 3″ if you quilt it at home.
- 03Choose the backing fabric width (42–44″ cotton, 60″, 108″ or 118″ wide back) or enter your own usable width.
- 04Read the yardage for the cheaper seam direction, compare it with the other layout in the diagram, then check the batting size and binding yardage.
Frequently asked questions
How many yards of fabric do I need for a queen quilt backing?
For a 90″ × 108″ queen top with 4″ extra per side, buy 8¼ yards of 42″ quilting cotton, sewn as three panels 98″ long with horizontal seams. With 108″ wide backing you need just 3¼ yards and no seams.
How many yards of fabric for a king quilt backing?
A 108″ × 108″ king needs a 116″ square backing with 4″ extra per side. That is 9¾ yards of 42″ fabric (three panels) or 6½ yards of 108″ wide back, because 116″ is wider than one width. Cut the extra to 3″ per side and a single length of 118″ wide back covers it in 3¼ yards.
How much 108 inch wide backing do I need for a queen quilt?
3¼ yards. The backing has to be 98″ × 116″, and 98″ fits inside the roughly 104″ of usable width, so one 116″ length does the job with no seam.
Is it cheaper to sew backing seams vertically or horizontally?
It depends on the size. On a queen with 42″ fabric, horizontal seams use 8¼ yards and vertical seams use 9¾, a saving of 1½ yards. On a twin, vertical wins at 5½ yards against 6½. The calculator checks both every time.
What size batting do I need for a queen quilt?
Plan on at least 98″ × 116″ for a longarm or 94″ × 112″ for home quilting. Both are bigger than a 90″ × 108″ queen batting package, so buy a king (120″ × 120″) or about 3¼ yards off a 120″ roll.
How much binding fabric do I need for a queen quilt?
A 90″ × 108″ queen has a 396″ perimeter, so you need about 406″ of binding. That is 11 strips of 2½″ × WOF, which comes to ⅞ yard of 42″ fabric.