Quilt Batting Calculator
Batting needs the same overhang as backing — and most batting rolls are wide enough to skip piecing entirely.
Batting overhang matches your backing
Batting gets the same overhang treatment as backing fabric — extra on every edge to load onto a frame and to leave room for the layers to shift slightly during quilting. Use the same overhang amount you used for your backing calculation so all three layers line up with room to spare.
Most batting doesn't need piecing
Unlike standard 42–44" quilting cotton, batting is typically sold in wide rolls specifically so it can cover most quilt widths in one piece. Seaming batting together is possible but usually avoided when it can be, since a batting seam can create a faint ridge or lump once it's quilted over.
Precut packaged batting is another option
Batting also comes in precut packages sized to standard bed dimensions: crib is roughly 45×60", throw around 60×60", twin near 72×90", full/queen close to 90×108", and king around 120×120". If your calculated size lands close to one of these, a precut package can be simpler than buying and cutting yardage off a roll.