Knots to Feet per Second Converter
Convert knots to feet per second — one knot is 1.688 ft/s. Results update as you type; exact factors shown.
One knot is 1.6878 feet per second — see the exact factor, not a rounded rule of thumb.
How the knots to feet per second converter works
Speeds convert through meters per second. 1 km/h is 1000/3600 m/s; 1 mph is 1609.344/3600 m/s; a knot is one nautical mile (1,852 m) per hour. Mach is shown against the standard sea-level speed of sound of 340.29 m/s and varies with altitude and temperature.
The US uses customary units (US gallon, short ton, °F) in daily life; NIST SP 811 gives the exact SI factors.
Common speed conversions
| From | To | Units |
|---|---|---|
| 1 kn | 1.6878 ft/s | knot to feet per second |
| 5 kn | 8.439 ft/s | knots to feet per second |
| 10 kn | 16.8781 ft/s | knots to feet per second |
| 15 kn | 25.3171 ft/s | knots to feet per second |
| 20 kn | 33.7562 ft/s | knots to feet per second |
| 25 kn | 42.1952 ft/s | knots to feet per second |
| 30 kn | 50.6343 ft/s | knots to feet per second |
| 40 kn | 67.5124 ft/s | knots to feet per second |
| 50 kn | 84.3905 ft/s | knots to feet per second |
| 100 kn | 168.781 ft/s | knots to feet per second |
| 200 kn | 337.562 ft/s | knots to feet per second |
| 500 kn | 843.9049 ft/s | knots to feet per second |
Units in this converter and their exact factors
| Unit | Symbol | One unit in meter per seconds |
|---|---|---|
| meter per second | m/s | 1 meter per second |
| kilometer per hour | km/h | 0.2777777778 meter per second |
| mile per hour | mph | 0.44704 meter per second |
| knot | kn | 0.5144444444 meter per second |
| foot per second | ft/s | 0.3048 meter per second |
| Mach (sea level, 15 °C) | Ma | 340.29 meter per second |
FAQFrequently asked questions about speed conversion
How many ft/s is 1 knot?
1.688 ft/s.
What is a knot?
One nautical mile per hour — 1,852 m/h, which is one minute of latitude an hour.
What is 30 knots in ft/s?
50.6 ft/s.
Where is ft/s used?
US ballistics, wind loading and some aviation performance figures.
What is 1 knot in mph?
1.151 mph.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Institute of Standards and Technology (NIST) — United States's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.