Fabric Conversions

Converting a fabric measurement has two halves, and only the first is arithmetic. One yard is exactly 0.9144 metres and one inch is exactly 25.4 millimetres, so the numbers convert without error. What does not convert cleanly is the cloth: a pattern written in yards was written for a roll sold by the yard, and those rolls are usually narrower than the metric ones.

Bolts of fabric on a shelf, out of focus, in soft daylight.

Converters

The ratios, exactly

Every term used on these pages is defined in the glossary.

These are definitions rather than measurements. The international yard and pound agreement of 1959 fixed the yard at 0.9144 metres exactly, which makes the inch exactly 25.4 millimetres. Neither figure is rounded, so no conversion on this site introduces error of its own — the only imprecision in any answer comes from your shop's cutting increment.

FromToMultiply byExact?
YardsMetres0.9144Yes
MetresYards1.0936133Recurring
InchesCentimetres2.54Yes
CentimetresInches0.3937008Recurring
FeetCentimetres30.48Yes

The recurring ones are recurring in one direction only, which is a useful thing to notice: if a conversion looks like it should be reversible with the same factor and is not, that is why. Going from 115 cm to 150 cm fabric cuts your length by about a quarter, but going back from 150 cm to 115 cm adds about a third.

Where the trade labels disagree with the maths

Roll widths are the part that catches people. The same cloth is labelled in both systems, both labels are rounded, and the two roundings do not agree. A fabric sold as "55 inch" is 139.7 cm and will be labelled 140; a fabric sold as "54 inch" is 137.16 cm and will be labelled 137. Those are two different fabrics that are routinely treated as one.

Nominal roll widths, and what they actually measure.
Sold as Also labelled Exact Typical use
36 in 90 cm 91.44 cm Quilting cottons, older dress fabrics
44 in 112 cm 111.76 cm Standard quilting cotton
45 in 115 cm 114.3 cm Dressmaking cottons, commercial patterns
54 in 137 cm 137.16 cm Upholstery, curtain lining
55 in 140 cm 139.7 cm Curtain and furnishing fabrics
60 in 150 cm 152.4 cm Knits, wide dress fabrics
108 in 274 cm 274.32 cm Wide-back quilting fabric

Over a single width the discrepancy is under 3 cm and rarely matters. Over four joined widths in a made-to-measure curtain it is more than a centimetre of finished width per seam, which is the sort of error nobody spots until the curtains are hung.

Converting length is not converting fabric

This is the failure worth guarding against. Take a pattern calling for 3 yards, convert it to 2.75 metres, round up to 2.8, and buy 2.8 metres of a fabric that happens to be 44 inches wide — and you have bought roughly half the cloth the pattern expects, because it assumed a wider roll.

The fabric width converter handles that second half by converting the area rather than the length. It also says when the conversion cannot be trusted, which is more often than most such tools admit: a directional print, a nap, or any single pattern piece wider than the narrower roll breaks the area equivalence outright.

For a project rather than a pattern, the fabric calculators take width and length together from the start, so no conversion step is needed. The exact ratios used here, and where each one comes from, are on the methodology page.