Definition
Fullness ratio
How much wider the fabric for a curtain is than the window or track it covers. A fullness ratio of 2 means the fabric is twice the width of the track, which is the common starting point for a gathered pencil pleat heading.
Lower ratios give a flatter, more contemporary look and higher ratios give deeper folds. Both change the fabric quantity a great deal, which is why the curtain calculator asks for it explicitly.
Tools that use this term
Curtain Fabric Calculator
Work out how much fabric curtains need from the window width, the fullness ratio, the drop and the pattern repeat.
Fabric Calculator
Work out how much fabric to buy for a project from its finished size, the seam allowance you are cutting and the width of the bolt you are buying.