Speed at sea is traditionally measured in knots. One knot equals one nautical mile per hour. A nautical mile is longer than a kilometer and measures exactly 1.852 km. This leads to the simple conversion:
1 knot = 1.852 km/h
With this value, knot speeds are easy to convert.
5 knots ≈ 9.26 km/h
10 knots ≈ 18.52 km/h
15 knots ≈ 27.78 km/h
20 knots ≈ 37.04 km/h
30 knots ≈ 55.56 km/h
On the water, speed feels very different from speed on land. A yacht traveling 20 knots feels much faster than 37 km/hin a car because water resistance, wind pressure and spray intensify the sensation. Even moderate speeds can feel energetic on a yacht.
Why knots are used at sea
The unit comes from early navigation. Sailors used a rope with knots tied at fixed intervals and let it run into the water. By counting how many knots passed through their hands in a set time, they calculated the vessel’s speed. The name “knot” remained even after navigation became digital.
Why km/h is not used
Maritime navigation follows a global standard:
Speed in knots
Distance in nautical miles
Position in degrees and minutes
Depth in meters or feet
Using unified measurements allows captains from all countries to communicate clearly and navigate consistently.
Practical meaning for guests
Understanding knot speed helps passengers make sense of:
Travel time between islands
Fuel planning
ETA to the next harbor
Wind forecasts, which are also given in knots
Wind speeds in knots are especially useful:
5–10 knots = light breeze
15–20 knots = good sailing wind
25+ knots = challenging conditions
Knowing how fast a knot is creates a clearer sense of movement at sea and helps guests understand how speed, comfort and safety work together on a yacht.
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