QUILT PLANNING / BACKING

How much backing fabric do I need?

Start with the backing dimensions, then count full-width fabric panels. Dividing the quilt area by fabric width misses seam losses and can underestimate your purchase.

Measure, allow, compare

  1. Measure the quilt top in both directions. Use the largest dimensions if it is not quite square.
  2. Add your quilter’s overage to both edges of each dimension. Four inches per side adds eight inches to width and length.
  3. Measure usable fabric width after selvages. Compare vertical and horizontal panel layouts.
  4. Include the fabric consumed by joins, convert total cut length to yards, and round the purchase up.

A 60 × 80 inch quilt

With 4 in per side, the required back is 68 × 88 in. Two 42 in panels joined with ½ in on each edge cover 83 in across. Cut each panel 88 in long: 176 ÷ 36 = 4.889 yd. Buying in eighths means 5 yd. The horizontal layout needs three 68 in cuts and rounds to 5¾ yd.

↔ Swipe or scroll sideways to compare all columns.

Backing yardage for example quilt sizes
Example quilt top42 in usable106 in usable wide-back
Crib · 36 × 52 in2 1/2 yd · 2 panels1 1/4 yd · 1 panel
Throw · 50 × 60 in3 1/4 yd · 2 panels1 5/8 yd · 1 panel
Twin · 70 × 90 in5 1/2 yd · 2 panels2 1/4 yd · 1 panel
Queen · 90 × 100 in8 1/4 yd · 3 panels3 yd · 1 panel
King · 108 × 108 in9 3/4 yd · 3 panels6 1/2 yd · 2 panels

Assumes 4 in extra on every side, ½ in seam allowance on each joined edge, and the lower-yardage full-panel layout. The wide-back column models a 108 in fabric with 106 in usable after trimming; measure your own cloth. A 90 × 100 in top needs a 98 × 108 in back: the 106 in width covers the 98 in side, so one 108 in length works. Purchases round up to the next ⅛ yd. Sizes are examples, not bed-size standards. Shrinkage, print matching and additional squaring waste are excluded.

What changes the estimate?

Wide-back fabric may cover one dimension without a seam. A directional print can rule out the otherwise shorter layout. Shrinkage and matching a repeating motif require extra planning: neither is included in these estimates. Measure after any intended prewashing and allow for squaring individual cuts.

Use the seam direction guide to compare layouts, or check wide-back against regular fabric before buying.

Two layouts for a 60 by 80 inch quiltTwo schematic full-panel layouts with 42 in usable fabric, 4 in overage per side and ½ in allowances on each joined edge. Dashed lines indicate seam orientation; panel spacing is illustrative, not a to-scale cut pattern. Purchases round up to ⅛ yd.Vertical seamsHorizontal seams2 × 88 in cuts · 5 yd3 × 68 in cuts · 5¾ yd
Two schematic full-panel layouts with 42 in usable fabric, 4 in overage per side and ½ in allowances on each joined edge. Dashed lines indicate seam orientation; panel spacing is illustrative, not a to-scale cut pattern. Purchases round up to ⅛ yd.

Use the backing calculator →

Read our calculation methods and limits. Examples use the same arithmetic as the calculators and are planning estimates, not independently field-tested sewing instructions. Confirm allowances with your quilter.