Heather Thomas

Determining Fabric Calculations for Quilts

Heather Thomas
Duration:   11  mins

How much of each color of fabric is needed to complete a design is generally given when you are working off of a purchased pattern. However, when designing your own quilt it can be difficult to know how much you will need. Heather Thomas shows you how to do basic fabric calculations to determine how much of each color or print of fabric you will need.


Before beginning the fabric calculations based on a quilt block or design, Heather explains how much workable fabric there is per yard of fabric purchased. This can vary depending on the width of fabric you are buying, but in general quilting cotton has approximately 40” of workable fabric width per yard. Heather then explains how to determine the amount of fabric needed to make one quilt block in a design. Once this is done, the amount of fabric needed for the one block can be multiplied by the number of blocks in the quilt.

Heather shows how to do the fabric calculations based on how the block is constructed, whether it is a four-patch, nine-patch, half square triangle or another common block construction. Heather also shows how to do fabric calculations for how much background fabric is needed, depending on your quilt design. She also explains how to add in extra amounts of fabric to account for any mistakes that may be made during the piecing process that require extra fabric.

Heather also gives a fun tip on how she adds fabric to her stash by rounding up the amount of fabric needed to the nearest full yard. Once you have the correct amount of fabric you can begin working on your quilt.