Length & size

Length and size converters

Convert between metric and imperial lengths: centimeters, inches, feet, meters, millimeters, kilometers and miles. Instant results for shopping, travel, construction and everyday measurements.

Last updated: May 2026

Metric and imperial

Most length conversions come down to one job: a spec sheet, product listing or map distance is in the wrong unit system. These are the most-used converters.

Smaller units

Millimeters and fractional inches come up in manufacturing, 3D printing, machining and detailed product specs.

When you need a length converter

Length is the most common source of metric versus imperial confusion. A screen listed in inches, a piece of furniture in centimeters, a road sign in miles, a product spec in millimeters — each one forces a conversion the moment you try to compare or order.

The most practical rule: pick one unit system and convert everything else into it before you start. Mixing halfway through a project is where mistakes happen.