The knot (kn) equals one nautical mile per hour or approximately 1.852 kilometers per hour, the universal speed unit for maritime and aviation navigation. Ship speeds, aircraft velocities, and wind speeds in meteorological reports all use knots as their standard measurement. One knot equals exactly 1.15078 miles per hour, reflecting the longer nautical mile compared to the statute mile.

Mach (Ma) is a dimensionless speed unit representing the ratio of an object's speed to the speed of sound in the surrounding medium. At sea level under standard conditions, Mach 1 equals approximately 343 meters per second or 1,235 kilometers per hour, though this varies with altitude and temperature. Supersonic aircraft travel above Mach 1, while hypersonic vehicles exceed Mach 5.