Curtain Fabric Calculator
Curtain fabric from the track width, fullness, panels and finished drop: whole widths, cut drops rounded to the pattern repeat, and lining when you want it.
How many fabric widths the curtains need at the fullness you choose, the cut drop with heading, hem and repeat, the total yards or metres, and the same for lining — every allowance entered by you.
Example: A 72 in track with 6 in returns at 2.25× on 54 in fabric needs 4 widths, 2 per panel; an 84 in drop with 8 in heading and hem rounds to four 25 in repeats: 400 in = 11.11 yd, lining 10.44 yd.
Widths first,
then the drop.
Why curtains are counted in fabric widths, what fullness means and where it comes from, how the cut drop is built and rounded to the repeat, and what lining adds.
Widths from fullness
The track or pole width, plus the returns to the wall and the overlap at the centre, is the width the curtains must cover flat. Fullness is how much fabric is gathered into that width — 2× means twice the track width of flat fabric. The flat width divided by the fabric width, rounded up, is the number of widths; they are shared equally between the panels, so a pair may need one more width than the sum alone. The actual fullness after rounding is shown; half widths are a hand decision.
The cut drop
Each width is cut to the finished drop plus the heading allowance at the top and the hem allowance at the bottom — both figures from your heading tape and your hem style, not assumed. A patterned fabric must be cut in whole repeats so that every width matches its neighbour: the cut drop is rounded up to a multiple of the repeat, and the page says how much of each width is for matching.
Lining
Lining is cut the same number of widths, at the finished drop plus a single allowance for its own heading and hem, and has no repeat. Blackout and thermal linings follow the same arithmetic; only their allowances differ, and those are yours to enter.
What the number does not settle
Fullness ratios for particular heading tapes are the tape maker’s figures; the page carries no table. Pattern matching across panels, weighting, interlining and the extra drop a heavy fabric takes when hung are not modelled. Inputs stay in your browser; the same anonymous usage counts as the rest of the site apply.