A nautical mile was originally one minute of latitude, which is why navigators use it with charts: one degree of latitude is 60 nautical miles. Since 1929 it has been defined as exactly 1,852 metres. Ships and aircraft measure speed in knots.
How to use the Nautical Mile Calculator
- Distance
- Speed
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the distance in nautical miles (or any unit) to convert it, and a speed in knots to see how long the passage takes.
Tips
- Use your own measured figures – fuel economy, speed and prices vary a lot with driving style, traffic, load and season.
- Pick the unit in each field’s menu (miles or kilometres, mpg or L/100 km); the calculator converts everything for you.
- Fill up to the brim twice and divide the distance by the fuel added to measure real fuel economy.
- For vehicle modifications, treat results as a starting point and confirm with the parts maker or a professional mechanic.
Common mistakes to avoid
- Mixing US and imperial (UK) gallons – a UK gallon is about 20% bigger.
- Using the advertised fuel economy instead of real-world figures.
- Forgetting tolls, parking and wear and tear when comparing driving with public transport.
Inputs explained
| Field | What to enter |
|---|---|
| Distance | Units: nmi, mi, km, m |
| Speed | Units: knots, mph, km/h |
What each result means
- Time at this speed = [Distance]÷[Speed]÷3600
- Degrees of latitude = [Distance]÷1852÷60
Formula
1 nautical mile = 1,852 m = 1.15078 mi = 6,076.1 ft1 knot = 1 nautical mile per hourDistance (nmi) = speed (kn) × time (h)Worked example
Inputs — Distance: 100 nmi; Speed: 12 knots.
Results — Distance in nautical miles = 100 nmi; In statute miles = 115.078 mi; In kilometres = 185.2 km; Time at this speed = 8 h 20 min; Degrees of latitude = 1.6667 °.
Frequently asked questions
Why is a nautical mile longer than a mile?
It is based on the Earth's circumference – one minute of latitude – rather than on 5,280 feet.
How fast is 1 knot?
1.15078 mph or 1.852 km/h.
Why do pilots use nautical miles?
Because they relate directly to latitude and longitude on charts.
What formula does the Nautical Mile Calculator use?
1 nautical mile = 1,852 m = 1.15078 mi = 6,076.1 ft.