Convert Knots (kn) to Miles Per Hour (mph)
1 knot equals 1.15078 miles per hour.
Knot to Mile Per Hour Converter
What Is a Knot?
The knot (kn or kt) is a unit of speed equal to one nautical mile per hour. It is used in maritime navigation, aviation, and meteorology worldwide. One knot = 1.852 km/h exactly, by international definition.
What Is a Mile per Hour?
The mile per hour (mph) is used for road speeds in the US and UK. One mph = 1.609344 km/h exactly.
Knots to mph Formula
The conversion formula is:
mph = knots × 1.150779
Derived from: 1 knot = 1.852 km/h and 1 mph = 1.609344 km/h, so 1 knot = 1.852 ÷ 1.609344 = 1.15077945... mph.
Worked Example
A ship travels at 25 knots. What is that in mph?
- Multiply: 25 × 1.15078 = 28.8 mph
Quick Estimation
Add 15% to the knot value. Example: 25 + 15% = 25 + 3.75 ≈ 28.8 mph. This shortcut is accurate within 0.1% — practically exact.
Common Use Cases
- Boating: Recreational sailors converting boat speed to road-speed terms for passengers. A fast motorboat at 30 knots = 34.5 mph.
- Aviation: Pilots communicating airspeed to non-aviation audiences. A cruising speed of 450 knots ≈ 518 mph.
- Weather reports: Hurricane and storm wind speeds are reported in knots internationally but mph in US media. A Category 1 hurricane starts at 64 knots = 74 mph.
Frequently Asked Questions
How many mph is 1 knot?
1.15078 mph. A knot is about 15% faster than a mph. Quick reference: 10 knots = 11.5 mph, 20 knots = 23 mph, 50 knots = 57.5 mph.
Why do sailors use knots instead of mph?
Knots are based on nautical miles, which are directly tied to Earth's geometry: 1 nautical mile = 1 minute of latitude. This makes navigation calculations simpler — distance, position, and speed all use the same base unit.
What is the difference between a knot and a nautical mile?
A nautical mile is a unit of distance (1,852 meters). A knot is a unit of speed (1 nautical mile per hour). Saying "knots per hour" is incorrect — a knot already includes "per hour."
What wind speed in knots is considered dangerous?
Gale force starts at 34 knots (39 mph). Storm force is 48 knots (55 mph). Hurricane force is 64 knots (74 mph). Small craft advisories are typically issued at 20–33 knots (23–38 mph).
Common Knot to Mile Per Hour Conversions
Knots to miles per hour Conversion Table
Reference table with common knots to miles per hour conversions. All values calculated with high precision.
Knots to Miles Per Hour Table
0.0001 to 12
Knots to Miles Per Hour Table
1 to 100000
Miles Per Hour to Knots Table
0.001 to 5
Miles Per Hour to Knots Table
10 to 1000000
Looking for the reverse? Convert Mile Per Hour to Knot
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Related in other categories:
- G-force to m/s² — Acceleration = change in speed ÷ time
- Hours to Days — Knots = nautical miles per hour (speed × time)
