Metric vs Imperial Sizing

Two measurement systems, one body — here's how to move between them without confusion.

The two systems

Imperial (inches, feet) is standard in the US. Metric (centimeters, meters) is standard almost everywhere else, including the UK for many everyday contexts despite imperial holding on in some areas.

The conversion factor

1 inch = 2.54 centimeters, exactly. To go from inches to cm, multiply by 2.54. To go from cm to inches, divide by 2.54.

Why it matters for sizing

US and UK size charts are usually built around inch measurements, while EU and most Asian size charts are built around centimeters. When a chart looks "off" by a strange amount, double-check which unit it's actually using.

Our calculators handle this for you

Every 7TShirts calculator that takes a measurement lets you toggle between inches and centimeters, so you can enter whichever unit your tape measure shows.