Sewing & Quilting Quilt Block Count Calculator
Created by: Emma Collins
Last updated:
Convert your target quilt dimensions into a practical block layout. Get rows, columns, total block count, and actual finished size with optional sashing and borders.
Quilt Block Count Calculator
SewingConvert target quilt size into rows, columns, and total blocks
Target Quilt Size
Layout Inputs
Related Calculators
What is a Quilt Block Count Calculator?
A Quilt Block Count Calculator converts your target quilt dimensions into a practical block layout. It recommends rows, columns, and total block count using your finished block size plus optional sashing and border widths.
This is useful when scaling patterns, planning custom quilts, or checking how many blocks you still need to complete.
Layout Formulas
Columns: round((Target Width − 2 × Border + Sashing) ÷ (Block Size + Sashing))
Rows: round((Target Length − 2 × Border + Sashing) ÷ (Block Size + Sashing))
Total Blocks: Columns × Rows
Actual Width: (Columns × Block Size) + ((Columns − 1) × Sashing) + (2 × Border)
Actual Length: (Rows × Block Size) + ((Rows − 1) × Sashing) + (2 × Border)
Example Calculation
For a 60-inch × 80-inch quilt using 10-inch finished blocks, 2-inch sashing, and 3-inch borders:
- Columns ≈ round((60 − 6 + 2) ÷ 12) = round(4.67) = 5
- Rows ≈ round((80 − 6 + 2) ÷ 12) = round(6.33) = 6
- Total blocks = 5 × 6 = 30
- Actual quilt size = 64 inches × 78 inches
Common Applications
- Pattern scaling: Resize quilts for crib, throw, twin, and queen sizes
- Project tracking: See how many blocks remain to finish a layout
- Design planning: Compare layouts with and without sashing
- Budgeting: Estimate time and fabric based on block count
Tips for Block Layout Planning
- Build one test block to verify true finished size before cutting all fabric
- Use consistent seam allowances to keep block size accurate
- Consider directional prints when planning row/column orientation
- Add a border when you are close to target size but need extra inches
Frequently Asked Questions
How many blocks do I need for my quilt size?
Block count depends on finished block size, quilt dimensions, and whether you include sashing and borders. This calculator estimates rows, columns, and total blocks to match your target dimensions.
Do I enter finished or unfinished block size?
Enter finished block size. Quilt planning is normally done in finished dimensions so layout and overall size calculations are accurate.
What is sashing in a quilt?
Sashing is the fabric strip between blocks. It increases final quilt size and changes layout spacing. Enter 0 if your blocks are sewn directly together.
How do borders affect block count?
Borders do not change block count directly, but they increase overall quilt dimensions. The calculator includes border width in the final size estimate.
Why is my actual quilt size slightly different?
Block layout must use whole rows and columns, so final size may be a bit larger or smaller than your exact target. The calculator shows the dimensional difference.
Can I use this for rectangular quilts?
Yes. Width and length are calculated independently, so rectangular, throw, and bed-size layouts are all supported.
Can this help with fabric planning?
Yes. Once block count is known, you can estimate unit totals and use related calculators for HSTs, fat quarters, and yardage.
Sources and References
- Fons & Porters Love of Quilting, Quilt Math Basics, 2024
- National Quilting Association, Block Sizing and Layout Standards, 2024
- American Patchwork & Quilting, Borders and Sashing Design Guide, 2024