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Quilt backing calculator
Estimate the continuous yardage needed for a pieced backing. The result includes overage but not print matching or shrinkage.
How the estimate works
The calculator adds your chosen overage to all four sides, finds how many full fabric-width panels are required, then multiplies that panel count by the backing length. The yardage is rounded up to the next eighth yard.
Ask the person quilting it. Longarmers often specify their own minimum overage. Wide-back fabric can also remove one or more seams.