Nautical Distance Calculator

Q: How do I convert between nautical miles and other units?

One nautical mile equals 1.852 kilometers, 1.15078 statute miles, or 6,076 feet. A nautical mile is defined as one minute of arc of latitude, making it naturally suited for navigation with charts and coordinates. - 1 nautical mile = 1.852 km exactly (international standard) - 1 nautical mile = 1.15078 statute miles - 1 nautical mile = 6,076.12 feet = 1,852 meters - 1 degree of latitude = 60 nautical miles (at the equator) - 1 knot = 1 nautical mile per hour = 1.852 km/h = 1.151 mph

Q: How do I estimate travel time for a sea passage?

Divide the distance in nautical miles by your average speed in knots. Sailboats typically average 5–7 knots on passage; motorsailers 7–9 knots; and powerboats 10–25 knots depending on size and sea conditions. - Travel time (hours) = Distance (nm) / Average Speed (knots) - Cruising sailboat: 5–7 knots average, 120–168 nm per day - Motorsailer / trawler: 7–9 knots, 168–216 nm per day - Sportfisher / express: 15–25 knots, 200–400 nm per day - Add 10–20% to estimated time for weather delays, calms, and current

Great-circle distance between coordinates

Preset Route

Departure Point

Latitude

Longitude

Destination Point

Latitude

Longitude

Cruise Speed (knots)

Great-Circle Distance

673.3

nautical miles

Kilometers

1,247

Statute Miles

774.8

Initial Bearing

135.4°

Travel Time at 6 kn

Hours

112.2

Days

4.7

Travel Hours by Speed

4 kn168 hrs

6 kn112 hrs

8 kn84 hrs

10 kn67 hrs

12 kn56 hrs

Popular Ocean Passages

Route	Distance (nm)	Days at 6 kn	Days at 10 kn
Miami → Nassau	184	1.3	0.8
NYC → Bermuda	650	4.5	2.7
Gibraltar → Canaries	620	4.3	2.6
Canaries → Caribbean	2,700	18.8	11.3
SF → Honolulu	2,090	14.5	8.7
Panama → Tahiti	4,350	30.2	18.1

What You'll Need

As an Amazon Associate, we earn from qualifying purchases.

Frequently Asked Questions

How do I calculate distance in nautical miles between two points?

Use the Haversine formula with latitude and longitude coordinates. The formula calculates the great-circle distance — the shortest path over the Earth’s surface — and returns the result in nautical miles by using Earth’s radius of 3,440 nm.

Great-circle distance is the shortest route on a sphere between two points
Earth radius for nautical calculations: 3,440.065 nautical miles
1 nautical mile = 1.852 km = 1.151 statute miles = 1 minute of latitude
New York to Bermuda: ~674 nm great-circle distance
Actual sailing distance is typically 5–15% longer due to wind routing and currents

Route	Great-Circle (nm)	Typical Sailing (nm)
Miami → Nassau	160	184
NYC → Bermuda	674	710
Gibraltar → Canaries	620	660
SF → Honolulu	2,090	2,200

What is the Haversine formula?

The Haversine formula calculates the great-circle distance between two points on a sphere given their longitudes and latitudes. It uses the law of haversines to avoid floating-point errors at small distances and is the standard formula for marine navigation.

a = sin²(Δlat/2) + cos(lat1) × cos(lat2) × sin²(Δlon/2)
c = 2 × atan2(√a, √(1-a))
distance = R × c, where R = Earth radius in desired units
More numerically stable than the spherical law of cosines for short distances
Accuracy is within 0.3% of actual distances on the WGS84 ellipsoid

What is the difference between great-circle and rhumb line distance?

A great-circle route is the shortest distance on a sphere but requires constantly changing compass heading. A rhumb line crosses all meridians at the same angle, making it easier to navigate but longer. For passages under 500 nm the difference is minimal.

Great-circle: shortest distance, curved line on a Mercator chart
Rhumb line: constant compass bearing, straight line on Mercator
For short distances (<500 nm), the difference is typically less than 1%
Transoceanic: great-circle can save 5–10% distance vs rhumb line
NY to London: great circle = 2,999 nm, rhumb line = 3,139 nm (4.5% longer)

How do I convert between nautical miles and other units?

One nautical mile equals 1.852 kilometers, 1.15078 statute miles, or 6,076 feet. A nautical mile is defined as one minute of arc of latitude, making it naturally suited for navigation with charts and coordinates.

1 nautical mile = 1.852 km exactly (international standard)
1 nautical mile = 1.15078 statute miles
1 nautical mile = 6,076.12 feet = 1,852 meters
1 degree of latitude = 60 nautical miles (at the equator)
1 knot = 1 nautical mile per hour = 1.852 km/h = 1.151 mph

How do I estimate travel time for a sea passage?

Divide the distance in nautical miles by your average speed in knots. Sailboats typically average 5–7 knots on passage; motorsailers 7–9 knots; and powerboats 10–25 knots depending on size and sea conditions.

Travel time (hours) = Distance (nm) / Average Speed (knots)
Cruising sailboat: 5–7 knots average, 120–168 nm per day
Motorsailer / trawler: 7–9 knots, 168–216 nm per day
Sportfisher / express: 15–25 knots, 200–400 nm per day
Add 10–20% to estimated time for weather delays, calms, and current

Show all questions

Example Calculations

1New York to Bermuda

Inputs

Departure Lat40.6892° N

Departure Lon74.0445° W

Destination Lat32.3078° N

Destination Lon64.7505° W

Cruise Speed6 knots

Result

Distance674 nm

Kilometers1,248 km

Bearing163° (SSE)

Travel Time112 hours (4.7 days)

Haversine distance from NYC (40.69°N, 74.04°W) to Bermuda (32.31°N, 64.75°W) = 674 nm. At 6 knots, travel time = 674/6 = 112 hours = 4.7 days.

2San Francisco to Honolulu

Inputs

Departure Lat37.7749° N

Departure Lon122.4194° W

Destination Lat21.3069° N

Destination Lon157.8583° W

Cruise Speed6 knots

Result

Distance2,087 nm

Kilometers3,865 km

Bearing228° (SW)

Travel Time348 hours (14.5 days)

Haversine distance from SF (37.77°N, 122.42°W) to Honolulu (21.31°N, 157.86°W) = 2,087 nm. At 6 knots = 348 hours = 14.5 days.

Show all examples

Formulas Used

Haversine Formula

d = R × 2 × atan2(√a, √(1-a))

Calculates the great-circle distance between two points on a sphere using latitude and longitude.

Where:

R= Earth radius (3,440.065 nautical miles)

a= sin²(Δlat/2) + cos(lat1)×cos(lat2)×sin²(Δlon/2)

Δlat= Difference in latitude in radians

Δlon= Difference in longitude in radians

Initial Bearing

θ = atan2(sin(Δlon)×cos(lat2), cos(lat1)×sin(lat2) - sin(lat1)×cos(lat2)×cos(Δlon))

Calculates the initial compass bearing from origin to destination along the great circle.

Where:

θ= Initial bearing in degrees (0° = North, 90° = East)

lat1, lat2= Latitudes of origin and destination in radians

Δlon= Difference in longitude in radians

Show all formulas

Understanding Nautical Distance and the Haversine Formula

Calculating distance at sea requires accounting for Earth’s curvature. Unlike road distances, the shortest path between two ocean points follows a great-circle arc. The Haversine formula provides an accurate way to compute this distance from GPS coordinates, and is the foundation of marine route planning.

The nautical mile itself is tied to Earth’s geometry: it equals one minute of arc along a meridian. This elegant definition means that latitude differences directly convert to distance — a 1-degree change in latitude always equals 60 nautical miles, making chart work intuitive for navigators.

For passage planning, the great-circle distance is the theoretical minimum. Actual sailing distances are longer due to weather routing (avoiding storms), favorable currents, island-hopping for rest stops, and the inability to sail directly into the wind. A common rule of thumb adds 10–15% to the great-circle distance for realistic passage estimates.

Related Calculators

Boat Fuel Calculator

Fuel consumption & range

Hull Speed Calculator

Theoretical max speed

Sail Area Calculator

Sail area & performance

Anchor Chain Calculator

Rode length & scope

Navigation ETA Calculator

Calculate your estimated time of arrival from distance, boat speed, and current conditions. Plan multi-waypoint passages with fuel stops and tidal gate windows.

Marine Holding Tank Calculator

Calculate your boat's holding tank capacity needs from crew size and trip duration. Plan pump-out schedules and estimate days of use before reaching capacity.

Related Resources

Boat Fuel Calculator

Plan fuel needs for your passage

Hull Speed Calculator

Find your displacement hull speed

Anchor Chain Calculator

Calculate rode length for anchoring

More Marine Calculators

Explore all marine and boating tools

View All

Last Updated: Mar 25, 2026

This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.

UseCalcPro

Nautical Distance Calculator

Great-circle distance between coordinates

Preset Route

Departure Point

Latitude

Longitude

Destination Point

Latitude

Longitude

Cruise Speed (knots)

Great-Circle Distance

673.3

nautical miles

Kilometers

1,247

Statute Miles

774.8

Initial Bearing

135.4°

Travel Time at 6 kn

Hours

112.2

Days

4.7

Travel Hours by Speed

4 kn168 hrs

6 kn112 hrs

8 kn84 hrs

10 kn67 hrs

12 kn56 hrs

Popular Ocean Passages

Route	Distance (nm)	Days at 6 kn	Days at 10 kn
Miami → Nassau	184	1.3	0.8
NYC → Bermuda	650	4.5	2.7
Gibraltar → Canaries	620	4.3	2.6
Canaries → Caribbean	2,700	18.8	11.3
SF → Honolulu	2,090	14.5	8.7
Panama → Tahiti	4,350	30.2	18.1

What You'll Need

Suunto A-30 Baseplate Compass with Clinometer

$25-$404.5

View on Amazon

Gill Marine Sailing Gloves Deckhand 3/4 Finger

$25-$354.4

View on Amazon

Davis Instruments Quick Reference Navigation Rules Card

$8-$124.6

View on Amazon

Suunto A-30 Baseplate Compass with Clinometer

$25-$404.5

View on Amazon

Gill Marine Sailing Gloves Deckhand 3/4 Finger

$25-$354.4

View on Amazon

Davis Instruments Quick Reference Navigation Rules Card

$8-$124.6

View on Amazon

As an Amazon Associate, we earn from qualifying purchases.

Frequently Asked Questions

How do I calculate distance in nautical miles between two points?

Great-circle distance is the shortest route on a sphere between two points
Earth radius for nautical calculations: 3,440.065 nautical miles
1 nautical mile = 1.852 km = 1.151 statute miles = 1 minute of latitude
New York to Bermuda: ~674 nm great-circle distance
Actual sailing distance is typically 5–15% longer due to wind routing and currents

Route	Great-Circle (nm)	Typical Sailing (nm)
Miami → Nassau	160	184
NYC → Bermuda	674	710
Gibraltar → Canaries	620	660
SF → Honolulu	2,090	2,200

What is the Haversine formula?

a = sin²(Δlat/2) + cos(lat1) × cos(lat2) × sin²(Δlon/2)
c = 2 × atan2(√a, √(1-a))
distance = R × c, where R = Earth radius in desired units
More numerically stable than the spherical law of cosines for short distances
Accuracy is within 0.3% of actual distances on the WGS84 ellipsoid

What is the difference between great-circle and rhumb line distance?

Great-circle: shortest distance, curved line on a Mercator chart
Rhumb line: constant compass bearing, straight line on Mercator
For short distances (<500 nm), the difference is typically less than 1%
Transoceanic: great-circle can save 5–10% distance vs rhumb line
NY to London: great circle = 2,999 nm, rhumb line = 3,139 nm (4.5% longer)

How do I convert between nautical miles and other units?

1 nautical mile = 1.852 km exactly (international standard)
1 nautical mile = 1.15078 statute miles
1 nautical mile = 6,076.12 feet = 1,852 meters
1 degree of latitude = 60 nautical miles (at the equator)
1 knot = 1 nautical mile per hour = 1.852 km/h = 1.151 mph

How do I estimate travel time for a sea passage?

Travel time (hours) = Distance (nm) / Average Speed (knots)
Cruising sailboat: 5–7 knots average, 120–168 nm per day
Motorsailer / trawler: 7–9 knots, 168–216 nm per day
Sportfisher / express: 15–25 knots, 200–400 nm per day
Add 10–20% to estimated time for weather delays, calms, and current

Show all questions

Example Calculations

1New York to Bermuda

Inputs

Departure Lat40.6892° N

Departure Lon74.0445° W

Destination Lat32.3078° N

Destination Lon64.7505° W

Cruise Speed6 knots

Result

Distance674 nm

Kilometers1,248 km

Bearing163° (SSE)

Travel Time112 hours (4.7 days)

Haversine distance from NYC (40.69°N, 74.04°W) to Bermuda (32.31°N, 64.75°W) = 674 nm. At 6 knots, travel time = 674/6 = 112 hours = 4.7 days.

2San Francisco to Honolulu

Inputs

Departure Lat37.7749° N

Departure Lon122.4194° W

Destination Lat21.3069° N

Destination Lon157.8583° W

Cruise Speed6 knots

Result

Distance2,087 nm

Kilometers3,865 km

Bearing228° (SW)

Travel Time348 hours (14.5 days)

Haversine distance from SF (37.77°N, 122.42°W) to Honolulu (21.31°N, 157.86°W) = 2,087 nm. At 6 knots = 348 hours = 14.5 days.

Show all examples

Formulas Used

Haversine Formula

d = R × 2 × atan2(√a, √(1-a))

Calculates the great-circle distance between two points on a sphere using latitude and longitude.

Where:

R= Earth radius (3,440.065 nautical miles)

a= sin²(Δlat/2) + cos(lat1)×cos(lat2)×sin²(Δlon/2)

Δlat= Difference in latitude in radians

Δlon= Difference in longitude in radians

Initial Bearing

θ = atan2(sin(Δlon)×cos(lat2), cos(lat1)×sin(lat2) - sin(lat1)×cos(lat2)×cos(Δlon))

Calculates the initial compass bearing from origin to destination along the great circle.

Where:

θ= Initial bearing in degrees (0° = North, 90° = East)

lat1, lat2= Latitudes of origin and destination in radians

Δlon= Difference in longitude in radians

Show all formulas

Understanding Nautical Distance and the Haversine Formula

Related Calculators

Boat Fuel Calculator

Fuel consumption & range

Hull Speed Calculator

Theoretical max speed

Sail Area Calculator

Sail area & performance

Anchor Chain Calculator

Rode length & scope

Navigation ETA Calculator

Calculate your estimated time of arrival from distance, boat speed, and current conditions. Plan multi-waypoint passages with fuel stops and tidal gate windows.

Marine Holding Tank Calculator

Calculate your boat's holding tank capacity needs from crew size and trip duration. Plan pump-out schedules and estimate days of use before reaching capacity.

Related Resources

Boat Fuel Calculator

Plan fuel needs for your passage

Hull Speed Calculator

Find your displacement hull speed

Anchor Chain Calculator

Calculate rode length for anchoring

More Marine Calculators

Explore all marine and boating tools

View All

Last Updated: Mar 25, 2026