Quilt Calculator - Calculate Backing, Batting & Binding
Calculate exact backing yardage, batting dimensions, and binding requirements for quilts with professional accuracy
Quilt Calculator
Results
What is a Quilt Calculator?
A Quilt Calculator is a free quilting tool that determines backing fabric yardage, batting dimensions, and binding requirements for quilts of any size. It calculates exact material needs based on quilt dimensions, fabric widths, and finishing specifications to ensure proper materials for quilting and binding.
This calculator works for:
- Quilt finishing - Calculate backing, batting, and binding for completed quilt tops before final assembly
- Project planning - Estimate total material costs and yardage requirements before purchasing finishing fabrics
- Custom quilts - Determine fabric needs for non-standard quilt sizes including bed quilts, wall hangings, and lap quilts
- Quilting prep - Ensure adequate backing extends beyond quilt top for proper tension during machine or hand quilting
Planning quilt blocks with HST units? Use our Half Square Triangle Calculator to determine cutting sizes and fabric requirements for HST blocks.
Calculating fabric for coordinating quilt components? The Fabric Calculator helps determine yardage for borders, sashing, and piecing fabrics.
Creating quilted bags or accessories? Our Bag Calculator determines fabric panel sizes for quilted purses and carriers.
How Quilt Calculator Works
The calculation uses these formulas:
Where:
- Margin = Extra backing extending beyond quilt edge (4-6 inches per side recommended)
- Batting = Middle layer, typically 4 inches larger than quilt top on all sides (8 inches total per dimension)
- Perimeter = Total distance around quilt edge (2 × width + 2 × length)
- +20 inches = Extra binding for joining strips and mitering corners with ease
For quilts wider than fabric width, backing requires piecing two or three panels. Calculator determines optimal panel layout and total yardage needed including seam allowances for piecing.
Key Concepts Explained
Backing Fabric
Bottom layer of quilt sandwich. Must extend 4-5 inches beyond quilt top on all sides to prevent shifting during quilting. Requires piecing for wide quilts.
Batting
Middle insulating layer. Available pre-packaged or by the yard. Must be larger than quilt top (4-6 inches per side) but slightly smaller than backing for ease of handling.
Binding
Fabric strips sewn around quilt edges to enclose raw edges. Cut on straight grain or bias. Standard widths are 2¼ to 2½ inches, creating approximately ½-inch finished binding.
Fabric Width
Standard quilting cotton is 42-44 inches wide. Wide backing fabric (60-108 inches) eliminates piecing for large quilts, saving time and reducing bulk at seams.
How to Use This Calculator
Measure Quilt Top
Input finished quilt top width and length in inches after piecing and borders
Select Fabric Width
Choose backing fabric width - standard cotton (42-45") or wide back (60-108")
Set Backing Margin
Choose 4-6 inches of backing extending beyond quilt edges for quilting ease
Select Binding Width
Choose binding strip width based on your preferred finished binding size
Calculate Materials
View backing yardage, batting size, and binding requirements instantly
Purchase Materials
Buy calculated amounts plus 10% extra for insurance against mistakes
Benefits of Using This Calculator
- Accurate material estimates - Calculate exact backing, batting, and binding requirements before shopping, preventing costly shortages or excess waste
- Cost planning - Determine total finishing costs by multiplying yardage by fabric price per yard for accurate project budgeting
- Multiple fabric widths - Compare standard versus wide backing costs and determine most economical option for your quilt size
- Professional results - Proper margins ensure adequate fabric for tension during quilting, preventing puckering and inadequate backing coverage
- Time savings - Eliminate mathematical errors and guesswork in material calculations, ensuring right-sized materials on first purchase
- Binding accuracy - Calculate exact binding length needed, accounting for mitered corners and joining strips without running short mid-project
Factors That Affect Your Results
- Fabric width selection - Wide backing (60-108 inches) eliminates seams for large quilts but costs more per yard than standard cotton requiring piecing
- Backing margin size - Machine quilting requires 4-5 inches minimum; longarm quilting needs 6-8 inches for proper mounting and tensioning on quilting frames
- Directional prints - Backing with directional patterns may require extra yardage to ensure design faces correct direction across pieced panels
- Batting shrinkage - Natural fiber battings (cotton, wool) shrink 3-5% when washed. Buy batting 2-3 inches larger than calculated if pre-washing batting
- Binding method - Single-fold binding uses less fabric than double-fold. Bias binding requires 25% more yardage than straight-grain binding for same perimeter
Frequently Asked Questions
How much backing fabric do I need for a quilt?
Add 8-10 inches to both quilt length and width for backing. For a 60x80 inch quilt top, purchase 68x88 inch backing (approximately 5 yards of 42-inch wide fabric). Extra allowance prevents shifting during quilting.
How do I calculate batting size for quilts?
Batting should be 4-6 inches larger than quilt top on all sides. For a 60x80 inch quilt, use 68x92 inch batting. This provides adequate working room for quilting and prevents exposed edges.
How much binding fabric do I need?
Calculate quilt perimeter and add 20 inches for joining and corners. Divide by 42 inches to get strips needed. A 60x80 inch quilt needs approximately 0.75 yards of fabric for 2.5-inch wide binding strips.
Should backing fabric be wider than the quilt top?
Yes, backing must extend 4-5 inches beyond quilt top on all sides (8-10 inches total per dimension). This prevents backing from pulling away during quilting and allows proper tension for machine or hand quilting.
How do I calculate yardage for large quilt backs?
For quilts wider than 42 inches, piece backing from two or three panels. For 60-inch wide backing, buy two lengths of fabric equaling quilt length plus 8-10 inches, totaling approximately 5 yards for an 80-inch quilt.