Distance Between Two Places (Address to Address)
Enter two addresses, places or coordinates, or click two points on the map, to measure the distance between them on the WGS84 ellipsoid in miles, kilometers and nautical miles, with initial and final compass bearings. It is the shortest surface distance, not a driving route.
Ready to Measure Distance
Choose two locations, search addresses, or load a verified sample route below.
New York, NY: 40.7128°, -74.0060°
Los Angeles, CA: 34.0522°, -118.2437°
Currently setting Point B. Click map to reposition pin.True WGS84 Geodesic Arc (Karney Solution)
Forward departure azimuth from Point A.
Arrival heading across converging meridians.
Constant compass angle (longer flight path).
Spherical Haversine formulas assume Earth is a perfect ball of radius 6,371,009 m. Open Map Lab computes exact ellipsoidal geodesics via Karney’s algorithm, accounting for Earth’s polar flattening (1/298.257).
How to use the distance calculator
- 1Enter two places
Type two addresses, places or coordinates, or click two points on the map.
- 2Measure on the WGS84 ellipsoid
The shortest surface distance is computed with Karney's geodesic method (GeographicLib), accurate to well under a meter.
- 3Read miles, km and bearings
See the distance in miles, kilometers and nautical miles with the initial and final compass bearings. It is not a driving route.
Straight-Line vs. Rhumb Line vs. Driving Distance
When you measure the distance between two locations on Earth, the answer depends entirely on which trajectory you follow across the physical terrain and mathematical coordinate space:
- Great-Circle / Geodesic Distance: The shortest physical path between two points across the curved surface of an oblate spheroid. Commercial airline flights follow geodesic paths because they minimize fuel burn and elapsed flight time. On a standard flat Mercator projection map, a geodesic appears as an upward curved arc.
- Rhumb Line (Loxodrome): A path of constant compass heading that intersects all longitudinal meridians at the same angle. While easier to navigate with a traditional magnetic compass on a nautical paper chart, a rhumb line is significantly longer than a geodesic on transoceanic voyages.
- Driving / Road Distance: The length of travel constrained to physical asphalt highway networks, bridges, one-way city street grids, and mountain passes. Driving distance is virtually always 15% to 45% longer than straight-line geodesic distance.
How the Distance Between Two Places Is Calculated
Most basic online distance calculators implement the Haversine formula. While computationally cheap, Haversine assumes that Earth is a geometrically perfect sphere with a static average radius of 6,371 kilometers (3,958.8 miles).
Real Earth is an oblate spheroid flattened at the poles by centrifugal force from planetary rotation. The equatorial radius (a = 6,378,137.0 m) is approximately 21.385 kilometers larger than the polar semi-minor axis (b = 6,356,752.3 m), with an ellipsoid flattening ratio of f = 1 / 298.257223563.
Why Open Map Lab Uses Charles Karney’s Geodesic Library
Published in the Journal of Geodesy (2013), Dr. Charles Karney’s algorithms solve the inverse and direct geodesic problems on the WGS84 reference ellipsoid with millimeter precision at any distance, including antipodal points.
Spherical Haversine models produce systematic distortion: they overestimate distances near the Equator by up to +0.2% and underestimate distances in polar regions (Alaska, Scandinavia, Canada) by up to −0.55%. On a 500-mile flight across Alaska, a Haversine calculator will misreport distance by nearly 2.75 miles. Open Map Lab uses Karney’s exact ellipsoidal solution on every calculation.
Why the Compass Bearing Changes Along the Route
If you depart New York City (JFK) flying toward London Heathrow (LHR), your initial compass departure heading is approximately 051° (northeast). However, as your aircraft approaches London, your heading has shifted to approximately 098° (east-southeast).
This occurs because longitudinal meridians are not parallel lines; they converge toward the Geographic North Pole. As an aircraft traverses converging meridians on a straight-line spatial path through three-dimensional space, the local angle between the flight path and true geographic north changes at every single waypoint.
The same geodesic path also fixes the true midpoint: if you need the midpoint between two locations rather than the full distance, it sits exactly halfway along this curve, not at the average of the two latitudes and longitudes.
Straight-Line Distance vs. IRS Mileage Rules
The idiom “as the crow flies” describes the direct, unimpeded straight-line path between two points. In practical commercial operations, understanding the relationship between crow-flies mileage and road mileage is critical:
- IRS Mileage Reimbursement (Rev. Proc. 2024-08): The Internal Revenue Service (IRS) permits standard business mileage tax deductions based strictly on actual odometer driving miles, not crow-flies distance. Deducting straight-line distance instead of actual driving mileage forfeits significant legal tax deductions.
- Circuity Factor: The ratio of road driving distance to straight-line distance (Road Distance / Straight-Line Distance). In gridded Midwestern plains, the circuity factor is typically 1.15 to 1.25 (meaning roads take 15% to 25% longer than a straight line). In coastal or mountainous terrain with fjords or canyons, the circuity factor routinely exceeds 1.60 to 2.00.
- Commercial Drone Delivery: Quadcopter and eVTOL drone logistics operators use geodesic distance buffers to assess battery range feasibility, factoring in headwind vectors and FAA Part 107 airspace restrictions.
Distance Calculation: Worked Example
Here is a formal benchmark calculation demonstrating Karney’s exact ellipsoidal solution for transoceanic aviation:
s_{12} = b \int_0^{\sigma_{12}} \sqrt{1 + k^2 \sin^2 \sigma} \, d\sigma \quad \text{(Karney WGS84 Ellipsoidal Integral)}- Evaluate reduced latitudes eta_1 and eta_2 on the WGS84 ellipsoid.
- Solve the inverse geodesic problem using 6th-order series expansion for sigma_{12}.
- Computed ellipsoidal distance: s12 = 5,554,412.8 meters.
- Convert to statute miles: 5,554,412.8 m ÷ 1,609.344 = 3,451.35 statute miles.
- Convert to nautical miles: 5,554,412.8 m ÷ 1,852.0 = 2,999.14 nautical miles.
Initial departure heading from JFK is 051.2° (northeast). Arrival heading at LHR is 098.4° (east-southeast). Flight tracks across eastern Canada and southern Greenland.
Distances Between Famous Cities (Table)
Reference geodesic distances, nautical miles, and estimated commercial airline block flight times:
World Metro Geodesic Flight Benchmarks
Computed using Charles Karney WGS84 ellipsoidal geodesics. Flight times assume 490 knot average commercial jet cruising speed.
| Airport Route | Statute Miles | Kilometers | Nautical Miles | Estimated Flight Time |
|---|---|---|---|---|
JFK → LHR | 3,451 mi | 5,554 km | 2,999 NM | ~6h 50m |
LAX → HND | 5,488 mi | 8,832 km | 4,769 NM | ~11h 20m |
ORD → CDG | 4,152 mi | 6,682 km | 3,608 NM | ~8h 15m |
SFO → SYD | 7,440 mi | 11,974 km | 6,465 NM | ~14h 45m |
MIA → GRU | 4,073 mi | 6,555 km | 3,539 NM | ~8h 25m |
Distance Between Two Places: Accuracy and Limitations
- Ground Transportation & Commute Times: Never calculate automobile travel times by dividing straight-line distance by highway speed limits. Use our Drive Time Map tool to account for traffic, intersections, and physical highway geometry.
- Fuel Planning & Dispatch: Certified maritime and aeronautical navigation requires considering headwinds/jetstreams, Great Circle Waypoint waypoints, and ETOPS emergency alternate airports.
- Real Estate Radius Searches: A house marketed as "5 miles from downtown" measured straight-line may require a 12-mile drive around bays, rivers, or highway bottlenecks.
Quick facts about the distance calculator
| Fact | Value | Notes |
|---|---|---|
| Math Formula | Haversine & Vincenty | Accounts for the spherical curvature of Earth |
| Earth Mean Radius | 6,371.0088 km | WGS84 geodetic standard radius |
| Units Supported | 5 Standard Units | Miles, Kilometers, Nautical Miles, Feet, Meters |
| Bearing Calculations | Initial, Final, Rhumb | True compass headings across converging meridians |
Edge cases and exceptions
Antipodal Points
Points located directly opposite each other on Earth (180° longitude apart) have infinite shortest paths. The calculator gracefully identifies antipodal distances of ~12,450 miles.
High-Latitude Distortion
Standard Mercator maps severely distort distances near the poles. Our WGS84 geodesic calculations (Karney / GeographicLib) stay accurate to nanometers on the ellipsoid even across the Arctic and Antarctic circles.
The distance calculator: worked examples
Flight Distance Calculation
Scenario: Calculating direct flight distance from New York (JFK) to London (LHR).
Outcome: Measures 3,451 statute miles (5,554 km / 2,999 nautical miles) along the great-circle arc.
Amateur Radio & Antenna Azimuth
Scenario: Aiming a directional beam antenna from Chicago to Tokyo.
Outcome: Determines initial heading of 326° (NNW) across Alaska rather than a naive flat-map straight line.
Frequently asked questions about the distance calculator
What is great-circle distance?
Great-circle distance is the shortest distance between two points on the surface of a sphere or ellipsoid, curved along the Earth's spherical surface.
Why is straight-line distance shorter than driving distance?
Straight-line ("as the crow flies") distance ignores roads, terrain, and rivers. Driving distances are typically 15% to 35% longer due to road network winding.
What is the difference between initial and final bearing?
Because lines of longitude converge at the poles, a great-circle flight path changes compass heading continuously. Initial bearing is your departure heading; final bearing is your arrival heading.
Can I share the calculated distance?
Yes. The coordinates of both points are encoded in the URL hash, allowing you to copy and share the link without creating an account.
What units does this distance calculator support?
Miles, kilometers, nautical miles, feet, and meters are all computed and displayed simultaneously.
How accurate is the distance calculation?
Distances use the WGS84 ellipsoid (Karney's geodesic algorithm), accurate to within millimeters for the model itself. The practical limit is the precision of the two locations you choose.
Haversine or Vincenty: which is better?
Haversine treats Earth as a sphere and can be off by up to about 0.5%. Ellipsoidal methods such as Vincenty and Karney follow the true Earth shape. Our study compares them across latitudes.
What is the shortest path between two points on Earth?
It is the geodesic, the arc of the great circle (on a sphere) or its ellipsoidal equivalent. On a flat map it often looks curved, especially on long east-west routes.
Why do flights follow curved paths on a flat map?
Great-circle routes are the shortest paths on a sphere, and a Mercator map stretches the poles, so the shortest route bends toward them. Winds and airspace rules also shape actual flight paths.
How do I convert miles to kilometers?
Multiply miles by 1.609344 to get kilometers. A nautical mile is exactly 1,852 meters, or about 1.15 statute miles.
Can I measure the distance from my current location?
Yes. Use your device location as the starting point or enter an address, then add the second place by search or by clicking the map.
Does elevation change the distance?
The calculation is along the ellipsoid surface at sea level, so hills and mountains are not included. Terrain adds a small amount to walking distance. Use the elevation profile tool to see the climb along a route.
How far is it across the United States?
New York to Los Angeles is about 2,445 miles (3,935 km) in a straight great-circle line, while the driving distance is closer to 2,800 miles.
What is the longest possible distance between two points on Earth?
The antipodal distance, roughly half Earth's circumference, is about 12,430 miles (20,004 km) along the surface. See the antipode finder for the opposite point of any location.
Can I use this for driving distance?
No, it measures straight-line distance. Roads add curves and detours, typically 15 to 30 percent in the US. See our guide to straight-line versus driving distance.
How do I get the distance between two coordinates?
Enter the coordinates in decimal degrees in each field (for example, 40.7128, -74.0060). The tool accepts addresses, place names and coordinates.
Keep exploring
What to do with this result
- Halfway Point Between Two PlacesUse this to find the halfway point between two places.
- Bearing Calculator — Forward Azimuth & Compass HeadingUse this to calculate a compass bearing.
- As the Crow Flies Distance Calculator (Straight Line)Use this to measure as-the-crow-flies distance.
- Drive Time Map (Travel Time Isochrone)Use this to map a drive-time area.
- Multi-Stop Route Distance CalculatorUse this to total a multi-stop route.
Related map tools
Blog posts, studies & methodology
- As the Crow Flies Meaning: Straight-Line vs Driving DistanceBlog · 7 min read
- Latitude vs Longitude: The Difference and How to Read ThemBlog · 9 min read
- Geodesic vs Haversine Distance VarianceStudy · Measured error between spherical and ellipsoidal distance.
- How we validate every calculationPublic benchmarks and test results.