Quilt CalculatorHow do you calculate binding for a quilt?
Add the quilt width and length, then double it to get the edge length. Add 10 inches for corners and joins. Divide by the usable fabric width, often 40 inches, and round up. That is your strip count. Multiply strips by strip width to get the fabric length.
This method comes from the Utah State University Extension binding guide. Their example is a 56 by 70 inch quilt. The edge plus 10 inches is 262 inches. That divided by 40 is 6.55, so you cut 7 strips. At 2 1/4 inches each, you need 15 3/4 inches of fabric. Our tool gives the same answer.
Binding formula
Total length = 2 x (width + length) + extra
Strips = total length / usable width, rounded up
Fabric = strips x strip width
Yards = fabric / 36, rounded up to 1/8
Binding strip width
Most quilters cut double fold binding strips at 2 1/4 or 2 1/2 inches. Use 2 1/4 inches for thin cotton batting. Use 2 1/2 inches for thicker batting or a heavy quilt. The width you pick changes the fabric you need but not the number of strips.
The Utah State double binding lesson gives these same two widths. A folded 2 1/2 inch strip sewn with a 1/4 inch seam makes a binding that shows a bit wider on the front.
Quilt binding chart
Values use 40 usable inches and 10 extra inches. Yards round up to the next 1/8.
| Quilt (in) | Total length (in) | Strips | Yards at 2 1/4 | Yards at 2 1/2 |
|---|---|---|---|---|
| 36 x 52 | 186 | 5 | 3/8 yd | 3/8 yd |
| 50 x 65 | 240 | 6 | 3/8 yd | 1/2 yd |
| 60 x 80 | 290 | 8 | 1/2 yd | 5/8 yd |
| 70 x 90 | 330 | 9 | 5/8 yd | 5/8 yd |
| 84 x 102 | 382 | 10 | 5/8 yd | 3/4 yd |
| 90 x 108 | 406 | 11 | 3/4 yd | 7/8 yd |
| 108 x 108 | 442 | 12 | 3/4 yd | 7/8 yd |
How to cut and join the strips
- Cut the number of strips the tool shows, each at your strip width, from selvage to selvage.
- Join strips end to end with diagonal seams. A diagonal seam spreads the bulk so it does not make a lump.
- Press the joins open. Fold the long strip in half with wrong sides together and press.
- Trim the batting and backing even with the quilt top before you sew on the binding.
- Start in the middle of one side and leave a tail. Stop 1/4 inch from each corner to fold a miter.
The extension guide also suggests laying the strip around the quilt first so no join lands on a corner.
Other quilt calculators
FAQ
How wide should I cut binding strips?
Utah State University Extension lists 2 1/4 inches for thin batting and 2 1/2 inches for thick batting. Wider strips give a fuller edge on a puffy quilt. Narrow strips give a crisp edge on a flat, thin quilt.
How many strips do I need to bind a queen quilt?
A 90 by 108 inch queen quilt has a 396 inch edge. Add 10 inches for joins and corners to get 406 inches. Divide by 40 usable inches and round up. You need 11 strips cut across the width of the fabric.
How much fabric do I need for binding?
Multiply the number of strips by the strip width. Eleven strips at 2 1/2 inches is 27 1/2 inches of fabric. Round up to 7/8 yard. Many quilters buy an extra 1/8 yard in case of a cutting mistake.
Why add extra inches to the binding length?
Each corner miter and each diagonal join uses some length. You also need tails to join the two ends. The extension guide says to add 7 to 12 inches. This tool uses 10 inches by default, and you can change it.
Do I need bias binding?
Only for curved or scalloped edges. Straight grain strips cut across the fabric work for quilts with straight sides, according to the Utah State guide. Bias strips stretch around curves but take more fabric and more cuts.
What is double fold binding?
Double fold, also called French binding, is a strip folded in half the long way before you sew it on. The two layers protect the edge, which gets the most wear on a quilt.