Napped Fabric Layout Calculator
Velvet, corduroy, brushed cloth and one-way prints need every piece laid the same way up, or the colour changes from panel to panel. Six 40 × 50 cm pieces upright on 110 cm fabric fit two across, three rows, 150 cm. Turned on their side they still fit two across (110 ÷ 50) in three rows, but each row is only 40 cm long, so 120 cm does it — and a napped fabric cannot claim that 30 cm. The fabric yardage calculator assumes you are free to turn pieces, which is why it quotes less.
Your numbers
Fabric needed
150cm
Length if pieces are turned
120cm
Per row
2
Formula
Fabric needed = ⌈Pieces needed ÷ ⌊Fabric width ÷ Piece width⌋⌉ × Piece length
Velvet reads darker with the nap running up and lighter with it running down; either is fine as long as the whole garment agrees. A large repeating print costs more again, because each piece needs up to one full repeat of extra length to match at the seams.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Piece width (cm)One piece across, as cut — seam allowance included. | 40 | 1 and up |
| Piece length (cm)One piece along, as cut — seam allowance included. | 50 | 1 and up |
| Pieces neededHow many pieces you need at that size. | 6 | 1 and up |
| Fabric width (cm)The fabric width; if it is sold folded, enter the opened width. | 110 | 1 and up |
Step by step
Quick reference table
Results when only Piece width (cm) changes and everything else stays put.
| Piece width (cm) | Fabric needed (cm) | Length if pieces are turned (cm) | Per row |
|---|---|---|---|
| 20 | 100 | 60 | 5 |
| 30 | 100 | 90 | 3 |
| 40 | 150 | 120 | 2 |
| 60 | 300 | 180 | 1 |
| 80 | 300 | 240 | 1 |
What each result means
| Result | At default values |
|---|---|
| Fabric needed (cm)Fabric length to buy, along the grain rather than across. | 150 |
| Length if pieces are turned (cm)Fabric length if the pieces were turned 90° — a figure a napped cloth cannot use. | 120 |
| Per rowPieces that sit side by side across the width. | 2 |
Common mistakes
Velvet reads darker with the nap running up and lighter with it running down; either is fine as long as the whole garment agrees. A large repeating print costs more again, because each piece needs up to one full repeat of extra length to match at the seams.
Glossary
- Piece width
- One piece across, as cut — seam allowance included.
- Piece length
- One piece along, as cut — seam allowance included.
- Pieces needed
- How many pieces you need at that size.
- Fabric width
- The fabric width; if it is sold folded, enter the opened width.
- Fabric needed
- Fabric length to buy, along the grain rather than across.
- Length if pieces are turned
- Fabric length if the pieces were turned 90° — a figure a napped cloth cannot use.
- Per row
- Pieces that sit side by side across the width.
Frequently asked questions
Q. How is Napped Fabric Layout Calculator calculated?
Fabric needed = ⌈Pieces needed ÷ ⌊Fabric width ÷ Piece width⌋⌉ × Piece length — Velvet, corduroy, brushed cloth and one-way prints need every piece laid the same way up, or the colour changes from panel to panel. Six 40 × 50 cm pieces upright on 110 cm fabric fit two across, three rows, 150 cm. Turned on their side they still fit two across (110 ÷ 50) in three rows, but each row is only 40 cm long, so 120 cm does it — and a napped fabric cannot claim that 30 cm. The fabric yardage calculator assumes you are free to turn pieces, which is why it quotes less.
Q. Can you walk through an example?
With Piece width 40cm, Piece length 50cm, Pieces needed 6, Fabric width 110cm, the answer is Fabric needed 150cm.
Q. What do I need to enter?
Enter Piece width, Piece length, Pieces needed, Fabric width. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Piece width (cm) moves the answer to Piece width (cm) 20 → Fabric needed (cm) 100 and Piece width (cm) 80 → Fabric needed (cm) 300. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
Velvet reads darker with the nap running up and lighter with it running down; either is fine as long as the whole garment agrees. A large repeating print costs more again, because each piece needs up to one full repeat of extra length to match at the seams.
Related calculators
Materials differ in density and absorption. If your label states a figure, use it — the defaults here are only common values.