Quilt Batting Calculator

Find the batting dimensions you need for your quilt top — minimum and recommended sizes.

How to Use the Quilt Batting Calculator

  • Enter your finished quilt top width and length in inches.
  • Select the overhang amount for each side. More overhang makes quilting easier and gives you room to fix mistakes. 6" per side is the most common recommendation.
  • Select the batting shrinkage factor based on the fiber content of your chosen batting.
  • Click Calculate Batting to see your minimum and recommended batting dimensions, plus which packaged batting sizes will work for your quilt.

Understanding Batting Overhang

  • 4" per side — Minimum for machine quilting on a home machine. Leaves little room for shifting.
  • 6" per side — Standard recommendation. Gives you comfortable working room when loading the quilt.
  • 8" per side — Best for hand quilting or if using a longarm quilting service. Provides maximum flexibility.

Batting Shrinkage Notes

  • Cotton batting can shrink 2–5% when washed. Many quilters pre-wash batting to prevent quilt puckering.
  • Polyester batting has virtually no shrinkage and is a good choice if you skip pre-washing.
  • The recommended batting size already accounts for the shrinkage percentage you selected.