The U.S. uses U.S. Customary Units, which are based on the British Imperial system from the 1800s. While the U.S. government passed the Metric Conversion Act in 1975, it made the transition voluntary.

Metric is the "preferred system for trade and commerce," but customary units remain the standard for road signs, consumer products, and the construction industry. You will still see metric units in science, medicine, and the military, as well as on nutrition labels and soda bottles (e.g., the 2-liter bottle).

. Liberia is technically an imperial-using nation, but the government has recently made public commitments to transition to the metric system to better align with its West African neighbors.

Myanmar (Burma) has historically used its own traditional units of measurement (like the viss for weight), alongside imperial units introduced during British colonial rule.

In recent years, the Myanmar has taken significant steps to adopt the metric system officially. While imperial units (like miles for distance) are still commonly seen, the country is officially in a state of transition toward metrication.