Countries that use the metric and imperial system for measurement

While these three countries continue to use the imperial system, both Liberia and Myanmar are gradually introducing metric units, which are already widely used in some contexts.

In the United States, metric is technically the preferred system, as established by the Metric Conversion Act of 1975, but the imperial system remains prevalent in everyday life.

The United Kingdom presents a unique case; it is officially metric, but imperial units are still commonly used, especially for distances, heights, and weights in daily life. For example, road signs in the UK display miles rather than kilometres, and people often use pounds and ounces for body weight.

The imperial system, with units like inches, feet, pounds, and gallons, traces its origins to everyday items or human body parts, making it less standardised and less easily divisible than the metric system. Supporters of the imperial system argue that its units feel more relatable, while critics see it as less practical for scientific and global consistency.

Conversely, some critics of the metric system, which was designed for straightforward conversion and reference, view it as arbitrary.

Overall, the global trend strongly favours the metric system, with increasing adoption even in the few countries where imperial units still hold sway.