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Curtain Fabric Calculator — Curtain Yardage
Calculate fabric needed for curtains with fullness, pattern repeat and hem allowances.
How We Calculate This
Curtain fabric is calculated by working out the total gathered width, dividing by fabric widths, then multiplying by the cut drop adjusted for pattern repeat.
The formula
Total width = Track width × Fullness ratio
Fabric widths per curtain = ceil(Total width ÷ Curtain count ÷ Fabric width)
Cut drop = Finished drop + Hem allowance + Heading allowance
Adjusted drop = ceil(Cut drop ÷ Pattern repeat) × Pattern repeat
Fabric = Total widths × Adjusted drop
Frequently Asked Questions
Pencil pleat curtains need 2-2.5x fullness. Pinch pleat (triple) needs 2-2.5x. Eyelet curtains need 1.5-2x. Tab top curtains need 1.5x. Wave heading needs 2x. More fullness gives a more luxurious look.
Measure from the top of the track or bottom of the pole ring to where you want the curtain to finish. For sill length, measure to 1cm above the sill. For below sill, add 15cm. For floor length, stop 1cm above the floor.
Pattern repeat is the distance before a print repeats. Each fabric width must be cut so patterns match horizontally when joined. You need to round up the cut drop to the next full pattern repeat, which uses more fabric.
Standard hem allowance is 15cm (for a double 7.5cm hem). Heading allowance is 8-15cm depending on the heading type. Pencil pleat tape needs 10cm, pinch pleat 15cm, and eyelet heading 10cm above the tape.
Most curtain fabrics are 137cm (54in) wide. Some are 280cm (110in) wide — these railroaded fabrics can be turned sideways so you may not need seams. Always check the fabric bolt width before calculating.
Related Calculators
Curtain Lining Calculator
Work out lining fabric and interlining for professional curtains.
Curtain Weight Calculator
Calculate the weight of finished curtains for track load capacity.
Tie-Back Calculator
Calculate fabric and dimensions for curtain tie-backs.
Tab Top Calculator
Calculate tab dimensions and fabric for tab-top curtains.
Eyelet Curtain Calculator
Calculate eyelet spacing, heading fabric and ring quantities.
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Last updated: February 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.