Knot to Foot per Second Converter
Enter a value to instantly convert between speed units.
1 Knot = 1.6878 Foot per Second
Key Formulas
Kilometer per Hour → Mile per Hour
mph = km/h × 0.621371Mile per Hour → Kilometer per Hour
km/h = mph × 1.60934Knot → Mile per Hour
mph = kn × 1.15078Mile per Hour → Knot
kn = mph × 0.868976Formula
ft/s = kn × 1.68781Maritime industries (especially in the US Navy and Coast Guard) often need to convert between knots and feet per second for engineering calculations, fluid dynamics analysis, and historical documentation. One knot = 1.68781 ft/s. This direct conversion bridges nautical speed conventions with customary engineering units used in propulsion and hydrodynamic design.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A destroyer escort at 5 knots = 8.44 ft/s — slow transit in heavy seas.
5 kn = 8.44 ft/s
A patrol boat at 10 knots = 16.88 ft/s — standard inshore patrol speed.
10 kn = 16.88 ft/s
A frigate at 20 knots = 33.76 ft/s — typical military transport speed.
20 kn = 33.76 ft/s
A fast attack craft at 30 knots = 50.64 ft/s — high-speed intercept operations.
30 kn = 50.64 ft/s