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Curtain Fabric Calculator

Curtains look simple until fullness, hems and pattern repeats all start competing for the same fabric. Enter your track width and finished length and this calculator turns them into a shop-ready fabric quantity.

It works out the number of balanced drops, includes the fabric used by headings, hems, returns and overlaps, and keeps patterned drops aligned. The result is shown in familiar metres or yards with a clear cut length for every drop.

Fabric to buy10.2 m
Drops4
Cut length per drop255 cm
Construction width440 cm
Pattern repeats per drop0
Full-width curtain drops

Side hems, outer returns, centre overlap and joining seams are included before the number of drops is selected.

How to use it

A clear result in five steps

  1. 1Measure the complete track or pole.
  2. 2Choose finished length and fullness.
  3. 3Enter usable fabric width.
  4. 4Confirm construction allowances.
  5. 5Enter the vertical repeat and review the drops.
Method

The maths, without the mystery

Construction width includes desired fullness plus side hems, returns and overlap. Drops increase until their joined usable width covers that requirement. Each drop is then rounded to a complete vertical repeat.

Questions

Frequently asked questions

Why are side hems included?

They consume cloth width and reduce the coverage available from each drop.

What is a return?

The fabric that wraps from the front edge back toward the wall.

Why round each drop to a repeat?

Every joined drop must begin at the same motif position.