MetraNestFrom the finished square to the cut square
Add the full hem allowance to each of the four edges. A finished side of 40 cm with 2 cm folded under on each edge gives a 44 cm square. Mitred corners do not reduce the dimensions of this starting square.
Use the fabric width actually available
Divide the fabric width by the cut side and keep only whole pieces. Use prepared fabric and exclude unusable selvedges. A slightly narrower width can remove a whole column: measure it before deciding how much to buy.
Allow for an incomplete final row
The number of rows is rounded up. Even if only one napkin remains to be cut, the final row needs one full cut side length. The calculation does not reuse offcuts for another design or add an allowance for pattern matching or shrinkage.
Cut side = finished side + 2 × hem allowance. Pieces per row = whole-number part of fabric width ÷ cut side. Rows = quantity ÷ pieces per row, rounded up. Cutting length = rows × cut side ÷ 100.
Six finished 40 cm napkins
With a 2 cm hem allowance on each edge, the cut squares measure 44 cm. Three fit across a 140 cm fabric width. Six napkins need two rows, or 88 cm of fabric. Rounding the purchase up to 10 cm increases this to 90 cm.
Details to check
- Add both folds of a double-fold hem.
- Prepare the fabric before measuring its usable width.
- Keep offcuts without subtracting them twice.
Frequently asked questions
Does this calculation work for rectangular napkins?
No, the pieces are square. A rectangle needs two dimensions and a suitable layout.
Is an extra allowance included?
Only rounding up to 10 cm is added to the cutting length. Plan a separate allowance if your project needs one.
A method you can check · Content review :
Each tool shows its formulas and assumptions. Worked examples let you repeat the calculation and understand how rounding works.