Enter the width and height of the quilt top into the calculator to determine the total yardage needed for the quilt backing; this calculator can also evaluate the width or height given the total yardage.

Quilt Backing Formula

The following formula is used to calculate the total yardage needed for a quilt backing:

Y = (W + 4) * (H + 4) / 36

Variables:

  • Y is the total yardage needed for the quilt backing
  • W is the width of the quilt top in inches
  • H is the height of the quilt top in inches

To calculate the total yardage needed for the quilt backing, add 4 inches to the width and 4 inches to the height of the quilt top. Multiply the adjusted width and height together, and divide the result by 36 to convert it to yards.

What is a Quilt Backing?

A quilt backing is the bottom layer of a quilt sandwich, a three-layer packet made up of the quilt top, the batting, and the backing. The backing is typically a large piece of fabric that is used to cover the back of the quilt. It can be a single, unpieced piece of fabric, but it’s also possible to piece together smaller cuts of fabric to create a larger backing.

The backing is usually made from a soft, durable material that can withstand repeated use and washing. It’s often a solid color or a simple print so as not to distract from the quilt top, but it can also be a more complex design or even a second quilt top. The backing is attached to the other layers of the quilt sandwich through a process called quilting, where the three layers are sewn together in a decorative pattern.

How to Calculate Quilt Backing?

The following steps outline how to calculate the Quilt Backing.


  1. First, determine the width of the quilt top (in inches).
  2. Next, determine the length of the quilt top (in inches).
  3. Next, determine the desired overhang of the quilt backing (in inches).
  4. Finally, calculate the quilt backing size by adding the width, length, and twice the overhang.
  5. After calculating the quilt backing size, you can purchase the appropriate amount of fabric based on the width of the fabric bolt (usually 42-44 inches) and the desired backing size.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Width of the quilt top (in inches) = 60

Length of the quilt top (in inches) = 80

Desired overhang of the quilt backing (in inches) = 6