01 / PLAN YOUR BACKING
Quilt backing calculator.
Calculate quilt backing yardage, compare horizontal and vertical panels, and plan batting dimensions in inches or centimeters.
Your measurements
A little room to be sure: check the measurements and assumptions before buying or cutting.
Whole-project shopping list Backing, binding & batting together
Edit backing, binding & batting settings
Review both tools’ settings, including any defaults. Edit backing & batting · Edit binding
Project & saved plans Example project
Save on device keeps one project. A new save replaces it; export a file to keep more projects.
THE MATH, UNPACKED
A good backing starts
with a little breathing room.
Backing is the full fabric layer behind the batting and quilt top. The usable width is what remains after the selvages are removed. The calculator adds your chosen overage on every side, then compares full-width panels in two orientations.
Read the full method →How is the fabric calculated?
For each layout, the sewn coverage is the total panel width minus two seam allowances for every join. Each full-width panel is cut to the required backing length in that orientation. The panel lengths are added and the purchase is rounded up.
A 60 × 80 inch example
With 4 inches extra per side, 42 inches of usable fabric width and 1/2-inch seam allowances, vertical piecing needs two 88-inch lengths: 176 inches of fabric. Rounded up to the next 1/8 yard, buy 5 yards. Horizontal piecing needs three 68-inch lengths, or 5 3/4 yards after rounding.
What is outside this estimate?
Print matching, shrinkage, trimming each panel square, diagonal backing, and layouts assembled from smaller offcuts are not included. The lowest-yardage layout is only the lowest among the two full-panel layouts compared here.
QUILT PARTS, AT A GLANCE
Where the backing sits.
The quilt top is the visible pieced layer, batting adds loft in the middle, backing covers the reverse, and binding wraps the outside edge.
How much backing fabric should I buy?
Compare these example sizes, then calculate with your measured quilt top and your own allowances.
↔ Swipe or scroll sideways to compare all columns.
| Example quilt top | 42 in usable | 106 in usable wide-back |
|---|---|---|
| Crib · 36 × 52 in | 2 1/2 yd · 2 panels | 1 1/4 yd · 1 panel |
| Throw · 50 × 60 in | 3 1/4 yd · 2 panels | 1 5/8 yd · 1 panel |
| Twin · 70 × 90 in | 5 1/2 yd · 2 panels | 2 1/4 yd · 1 panel |
| Queen · 90 × 100 in | 8 1/4 yd · 3 panels | 3 yd · 1 panel |
| King · 108 × 108 in | 9 3/4 yd · 3 panels | 6 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.
42-inch cotton or 108-inch wide-back?
The calculator needs usable width after selvages, not the bolt label. Our presets use 42 in and 106 in usable width. Wide-back can remove seams, but a large king backing may still need piecing. Compare the total cost as well as yardage.
Which seam direction saves fabric?
Vertical seams join panels side by side; horizontal seams stack them. The shorter purchase depends on the quilt dimensions and seam take-up. Auto compares both full-panel layouts; lock a direction for a one-way print or your quilter’s requirements.
How much extra backing per side?
Four inches per side is the starting value in this tool, not a universal requirement. A 60 × 80 in top becomes 68 × 88 in. Confirm loading allowance with your longarm service before choosing fabric.
See a complete illustrated quilt-finishing example →