Quilt Backing Calculator
Standard Quilt Sizes & Backing Yardage
Yardage includes 4-inch overhang per side. Based on 44-inch fabric width.
| Quilt Size | Top Dimensions | Backing Needed | Yards (44") | Yards (108") |
|---|---|---|---|---|
| Baby / Crib | 36" × 52" | 44" × 60" | 3.4 yd | 1.7 yd |
| Throw | 50" × 65" | 58" × 73" | 4.1 yd | 2.1 yd |
| Twin | 68" × 86" | 76" × 94" | 5.3 yd | 2.7 yd |
| Full | 80" × 90" | 88" × 98" | 5.5 yd | 2.8 yd |
| Queen | 86" × 96" | 94" × 104" | 5.8 yd | 3.0 yd |
| King | 104" × 96" | 112" × 104" | 9.3 yd | 3.0 yd |
| Cal King | 104" × 108" | 112" × 116" | 9.7 yd | 3.3 yd |
| Lap Quilt | 40" × 56" | 48" × 64" | 3.6 yd | 1.8 yd |
| Table Runner | 16" × 48" | 24" × 56" | 1.6 yd | 1.6 yd |
How We Calculate This
This quilt backing calculator uses established formulas and industry-standard data to provide accurate estimates.
- Enter your specific values into the calculator fields above
- Our algorithm applies the relevant formulas using your inputs
- Results are calculated instantly in your browser — nothing is sent to a server
- Review the detailed breakdown to understand how each factor affects your result
These calculations are estimates based on standard formulas. For critical decisions, always consult a qualified professional.
How to Convert Oven Recipes to Air Fryer
Quilt backing must be larger than the quilt top on all sides to allow for quilting shift. The backing fabric width determines whether seams are needed.
The basic rule:
- Add 4 inches of overhang on each side (8 inches total to width and length)
- If the backing width needed exceeds the fabric bolt width, you need seamed panels
- For standard 42-44" fabric, most quilts wider than 38" need at least one seam
Use 108-inch wide backing fabric to avoid seams on most quilts. This calculator figures out the optimal panel layout and total yardage automatically.
When Would You Use This Calculator?
This quilt backing calculator is designed for anyone who needs quick, reliable estimates without complex spreadsheets or professional consultations.
- When you need a quick estimate before committing to a purchase or project
- When comparing different options or scenarios side by side
- When planning a budget and need to understand potential costs
- When you want to verify a quote or estimate you've received from a professional
- When teaching or learning about the concepts behind these calculations
Frequently Asked Questions
How much bigger should quilt backing be than the quilt top?
Standard practice is 4 inches extra on each side, making the backing 8 inches wider and 8 inches longer than the quilt top. Longarm quilters often request 4-6 inches extra per side. Check with your quilter for their specific requirements.
How do I piece quilt backing with standard width fabric?
Cut two or three lengths of fabric to the needed backing length, then sew them together along the selvage edges with a 1/2-inch seam. Press seams open to reduce bulk. Place seams off-center for a cleaner look.
What is wide quilt backing fabric?
Wide backing fabric is typically 108 inches (3 yards) wide, specifically made for quilt backs. It eliminates the need for seams on most quilt sizes. It comes in cotton, cotton blends, and is available in many prints and solids.
How do I calculate batting size for my quilt?
Batting should be the same size as your backing — quilt top dimensions plus 4 inches on each side. For a 60×80-inch quilt top, you need batting at least 68×88 inches. Buy the next standard batting size up from your needs.
Should I pre-wash my quilt backing fabric?
If you plan to wash the finished quilt, pre-washing is recommended to prevent uneven shrinkage between the top and backing. Most quilting cotton shrinks 3-5%. If you want the crinkled antique look, skip pre-washing.
How do I calculate backing for a king-size quilt?
A king-size quilt is typically 104×96 inches. With 4-inch overhang, you need 112×104-inch backing. With 44-inch fabric, that requires 3 widths sewn together: 3 panels × 112 inches = 9.3 yards. Or use 108-inch wide backing for just 3.1 yards with no seams.