How to Calculate Quilt Binding (With a Size Chart)

Quick answer: add up all four sides of your quilt, add about 12 inches, and divide by 42 to get the number of strips to cut. Multiply the number of strips by your strip width to get the fabric you need. A 60 × 72 inch throw needs 7 strips, which is about ½ yard of fabric.

That's the whole method. The rest of this guide explains each step, gives a ready-made chart for standard quilt sizes, and covers the few situations where the simple formula leaves you short.

Step 1: Find the perimeter

Measure your finished quilt top after it has been quilted and trimmed, not the pattern size. Quilting draws the fabric in, and a quilt that started at 60 × 72 inches can easily finish half an inch to an inch smaller each way.

The perimeter is the distance all the way around:

perimeter = 2 × width + 2 × length

For a 60 × 72 inch throw, that's 2 × 60 + 2 × 72 = 264 inches.

Step 2: Add extra length

Binding needs more than the perimeter, for three reasons:

• Diagonal joins. Strips are joined with 45° seams so the bulk spreads out. Each join uses a couple of inches.
• Mitred corners. Each fold at a corner takes up a little length.
• The final join. You need a tail at each end, usually 8 to 10 inches, to overlap and sew the ends together.

Adding 10 to 15 inches covers all three. Twelve is a safe default, so our throw needs 276 inches of binding.

Step 3: Work out how many strips to cut

Binding strips are normally cut across the width of the fabric, from selvage to selvage. Quilting cotton is sold 42 to 44 inches wide, but once the selvages are trimmed you can count on about 42 usable inches per strip. If your fabric is narrower after washing, measure it and use the real number.

strips = binding length ÷ usable fabric width, rounded up

For our throw: 276 ÷ 42 = 6.57, so cut 7 strips. Always round up. Six strips would leave you about 24 inches short, which is a very frustrating thing to discover at the final corner.

Step 4: Convert strips to fabric

fabric needed = number of strips × strip width

At 2½ inch strips: 7 × 2.5 = 17.5 inches. One yard is 36 inches, so that's 0.49 yards. Most shops cut in ⅛ yard steps, so buy ½ yard.

Binding chart for standard quilt sizes

This chart uses the same method: 12 inches extra and 42 usable inches per strip, with fabric rounded up to the nearest ⅛ yard. Quilt sizes vary between patterns, so treat these as typical sizes.

Quilt	Size (inches)	Binding length	Strips	Fabric at 2¼″	Fabric at 2½″
Baby	36 × 48	180″	5	⅜ yd	⅜ yd
Crib	45 × 60	222″	6	⅜ yd	½ yd
Throw	60 × 72	276″	7	½ yd	½ yd
Twin	70 × 90	332″	8	½ yd	⅝ yd
Full	80 × 90	352″	9	⅝ yd	⅝ yd
Queen	90 × 108	408″	10	⅝ yd	¾ yd
King	108 × 108	444″	11	¾ yd	⅞ yd

If your quilt isn't one of these sizes, the quilt binding calculator works it out for any dimensions, in inches or centimetres.

Which strip width should you use?

2½ inches is the most common choice for double-fold binding. It's forgiving, covers thicker batting comfortably and is easier to handle if you're new to binding.

2¼ inches gives a narrower, snugger binding that many experienced quilters prefer, especially with thin cotton batting. It uses slightly less fabric, which occasionally drops you down an ⅛ yard, as the chart shows for crib, twin and queen quilts.

If you use a thick or high-loft batting, consider going wider, to 2¾ inches, so the binding wraps fully around the edge.

When the simple formula isn't enough

Bias binding. Bias strips are cut at 45° to the grain. They stretch around curves, so you need them for scalloped or rounded edges, but cutting on the bias leaves triangle-shaped waste at the edges of your fabric. Buy about ¼ yard more than the chart suggests, or use a continuous bias method.

Directional or striped fabric. If you want stripes to run the same way around the whole quilt, or need to match a print, you'll lose some length at every join. Add another strip.

Fabric that shrinks. If you prewash, buy an extra ⅛ yard. Cotton can shrink 3–5% in each direction, which can cost you an inch or two per strip.

Scrappy binding. If you're piecing binding from leftovers, the strip count doesn't apply. Instead, join pieces until you have the full binding length from Step 2, then add a little more.

A quick check before you cut

Before cutting the last strip, lay your joined binding loosely around the quilt edge. You should have at least 8 to 10 inches of overlap at the ends. If you don't, cut one more strip now rather than piecing in a short scrap later.

Metric example

For a 150 × 200 cm quilt with 6 cm strips, about 107 cm of usable fabric width and 30 cm extra:

1. Perimeter: 2 × (150 + 200) = 700 cm. With 30 cm extra: 730 cm.
2. Strips: 730 ÷ 107 = 6.8, so cut 7 strips.
3. Fabric: 7 × 6 cm = 42 cm, so buy 0.5 m.