Quilt backing calculator.
Compare both seam directions before you cut.
Your measurements
The worked example below explains a complete fabric estimate. Enable JavaScript to calculate with your own measurements.
Planning estimate. Check measurements before buying or cutting. Terms of use.
A useful estimate.
A considered cut.
Start with usable width
Fabric labels may include the selvages. Enter the width you can actually use, and measure your quilt in more than one place.
Leave room for your process
Estimates exclude shrinkage, print matching and cutting mistakes. Check the layout and your fabric direction before buying.
See how we calculate ↗Backing for a 60 × 80 inch quilt
With 4 inches extra on every side, the backing must cover 68 × 88 inches. Suppose your fabric has 42 usable inches across the roll and you sew with a ½ inch seam allowance.
- Two lengthwise panels give 42 + 42 − 1 = 83 inches of joined width. That covers the required 68 inches.
- Cut both panels 88 inches long. Total fabric length is 2 × 88 = 176 inches.
- 176 ÷ 36 = 4.888… yards. Round up to the next eighth: 4⅞ is too short; buy at least 5 yards.
In the other orientation, three panels 68 inches long use 204 inches of fabric, rounded up to 5¾ yards. The lower-yardage option saves ¾ yard in this example, but print direction or your quilter’s instructions may determine which layout to use.
Read the panel measurements first
The result gives full-width cuts, not a promise that every scrap will be used. After joining, trim excess to the required backing size. The seam diagram is schematic: use the written panel dimensions for cutting.
When one panel is enough
If the usable fabric width covers the backing width, one piece may be enough. A fabric sold as “wide backing” still needs its usable width measured. Turning the fabric can change which dimension must fit across the roll.
What this estimate excludes
Print repeats, matching motifs, diagonal piecing, prewashing shrinkage and squaring-up losses are not calculated. If you need extra for any of these, plan that separately. Ask your quilting service how much overage and which seam direction they require.