A knot is one nautical mile per hour.
Knots to m/s Converter — kn to m/s
Convert Knots (kn) to m/s (m/s) using the exact conversion factor (1 knots = 0.5144444444 m/s). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Knots to m/s converter
Converter
Speed Converter
Convert road, aviation, marine, lab, and scientific speed units.
Context values
Some unit families need one extra value for a physically accurate result.
Meters per second.
Result = input x 0.5144444444 / 1.
Speed uses meters per second as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Knots to m/s
Knots and m/s both describe speed, and the conversion matters whenever a maritime or aviation speed (knots) needs to be compared against a road speed (mph). Knots is typically associated with used internationally in maritime navigation and aviation, while m/s is typically associated with standard scientific speed unit worldwide.
Formula
m/s = knots × 0.514444444444
This factor comes from each unit's defined relationship to the category's base unit: 1 knots equals 0.514444444444 base units, and 1 m/s equals 1 base unit, so dividing one by the other gives the direct knots-to-m/s factor of 0.514444444444.
Simple example
1 kn × 0.5144444444 = 0.5144444444 m/s
1 knots = 0.5144444444 m/s.
Real-world example
10 kn × 0.5144444444 = 5.144444444 m/s
10 knots = 5.144444444 m/s.
Conversion table
| Knots (kn) | m/s (m/s) |
|---|---|
| 1 kn | 0.5144444444 m/s |
| 5 kn | 2.572222222 m/s |
| 10 kn | 5.144444444 m/s |
| 25 kn | 12.86111111 m/s |
| 50 kn | 25.72222222 m/s |
| 100 kn | 51.44444444 m/s |
Reverse conversion: m/s to Knots
0.5144444444 m/s × 1.943844492 = 0.9999999999 kn
0.5144444444 m/s = 0.9999999999 knots.
knots = m/s × 1.94384449244
For a page dedicated to this direction, see m/s to Knots.
Knots vs. m/s
| Aspect | Knots | m/s |
|---|---|---|
| Family | Non-SI unit accepted for use with SI (maritime/aviation) | SI derived unit |
| Typical use | Ship and boat speed in marine navigation | Scientific and engineering speed/velocity calculations |
| Where it's used | Used internationally in maritime navigation and aviation | Standard scientific speed unit worldwide |
Understanding the Knots
Knots (kn) measures speed. A knot is one nautical mile per hour; since the nautical mile is exactly 1,852 meters, a knot is exactly 1,852/3,600 m/s. It is classified as a Non-SI unit accepted for use with SI (maritime/aviation).
Where it's used: Used internationally in maritime navigation and aviation
Uses of the Knots today
- Ship and boat speed in marine navigation
- Aircraft airspeed and wind speed reporting in aviation
- Marine weather forecasts (wind speed)
History of the Knots
The knot gets its name from an old nautical method of measuring speed: sailors trailed a 'log line' with evenly spaced knots behind a ship and counted how many knots paid out over a fixed time, giving a direct speed reading in 'knots.'
The nautical mile it's based on was itself standardized internationally in 1929 (the International Nautical Mile, 1,852 m exactly), tying the knot to a precise value still used in shipping and aviation today.
Historical origin. Knots was not the invention of a single named person; it developed through the process described above.
Understanding the m/s
m/s (m/s) measures speed. The meter per second is the SI derived unit of speed: one meter of distance per second of time. It is classified as a SI derived unit.
Where it's used: Standard scientific speed unit worldwide
Uses of the m/s today
- Scientific and engineering speed/velocity calculations
- Meteorology (wind speed, alongside km/h and knots)
- Physics education and calculations
History of the m/s
As a coherent SI derived unit, meters per second follows automatically from the meter and second, the SI base units of length and time, without an independent historical origin.
Historical origin. m/s was not the invention of a single named person; it developed through the process described above.
Knots — sources
- BIPM SI Brochure — Non-SI units accepted for use with SI — Lists the knot among accepted non-SI speed units.
m/s — sources
- BIPM SI Brochure — Coherent derived units — Defines m/s as the SI unit of speed.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many m/s are in 1 knots?
1 knots equals 0.5144444444 m/s, using the exact defined conversion factor rather than an estimate.
How do I convert knots to m/s?
Multiply the knots value by 0.5144444444. The converter above does this instantly to whatever precision you set.
How do I convert m/s back to knots?
Use the reverse factor: 1 m/s equals 1.943844492 knots. You can also use the swap control in the converter above to flip the direction instantly.
What is a knots?
Knots (kn) measures speed. A knot is one nautical mile per hour; since the nautical mile is exactly 1,852 meters, a knot is exactly 1,852/3,600 m/s. It is classified as a Non-SI unit accepted for use with SI (maritime/aviation).
What is a m/s?
m/s (m/s) measures speed. The meter per second is the SI derived unit of speed: one meter of distance per second of time. It is classified as a SI derived unit.
Is the knots to m/s conversion exact?
Yes. A knot is one nautical mile per hour; since the nautical mile is exactly 1,852 meters, a knot is exactly 1,852/3,600 m/s. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the knots still used today?
Used internationally in maritime navigation and aviation