Ten practical calculators

Sewing tools

Plan the cut, see the formula, and check the result before buying fabric.

Fabric planning

Lay out repeated rectangular cuts on a fabric width and estimate the yards to buy, including rotation and nap.

Compare both legal orientations for repeated rectangular cuts and convert the tighter plan into purchase yards.

Round each panel to a full vertical repeat and add the extra fabric needed to match a print at the seams.

Estimate bias or straight-grain strip length, cut width, joins, and the fabric needed for continuous binding.

Add independent seam and hem allowances to a finished width and height to get the cut size before you mark fabric.

Find the reprint percentage when a PDF pattern calibration square prints larger or smaller than the size marked on the page.

Calculate waist and hem radii for a quarter, half, or full circle skirt and the fabric width that footprint needs.

Convert a finished width and fullness ratio into gathered or pleated source width, take-up, and complete pleat repeats.

Estimate curtain yardage from track width, fullness, fabric width, header and hem allowances, and vertical pattern repeat.

Estimate yardage for an envelope or zippered cushion cover, including seam allowance, back overlap, and optional piping.