Kilometers per hour (km/h) is the most common speed unit outside the United States, displayed on speedometers and road signs across Europe, Asia, and most of the world. Highway speed limits, weather reports for wind speeds, and vehicle performance figures in these regions all use km/h. One kilometer per hour equals approximately 0.2778 meters per second or about 0.6214 miles per hour.

Feet per second (ft/s) is an imperial speed unit commonly used in ballistics, fluid dynamics, and engineering calculations within the United States. Projectile velocities, pipe flow rates, and conveyor belt speeds are often expressed in ft/s in American technical documentation. One foot per second equals exactly 0.3048 meters per second or about 0.6818 miles per hour.