Latitude/Longitude Distance Converter

Calculate the straight-line distance between two geographical points

Point A
From
Point B
To
Distance miles
2448.78
Kilometers
3941.29
Miles
2448.78
Meters
3941294.22
Nautical Miles
2128.12

About This Tool

This calculator uses the Haversine formula to compute the distance between two points on the Earth's surface, giving the "as-the-crow-flies" distance (the shortest distance between two points over the Earth's surface).

Real-World Use Cases
  • Navigation: Calculate distances between cities or landmarks
  • Flight Planning: Estimate flight distances between airports
  • Geocaching: Determine distances between geocache locations
  • Outdoor Adventures: Plan hiking, biking, or sailing routes
  • Education: Learn about geography and spherical geometry
Technical Details

The Haversine formula calculates the great-circle distance between two points on a sphere from their longitudes and latitudes. It accounts for the curvature of the Earth, providing more accurate results than simple planar geometry for longer distances.

Limitations
  • Does not account for terrain elevation changes
  • Assumes a perfect sphere (Earth is actually an oblate spheroid)
  • Does not consider actual travel routes (roads, paths, etc.)
Haversine Formula

The formula used in this calculator:

a = sin²(Δφ/2) + cos(φ₁) * cos(φ₂) * sin²(Δλ/2)
c = 2 * atan2(√a, √(1−a))
d = R * c

Where:
φ = latitude, λ = longitude
R = Earth's radius (mean radius = 6,371 km)

Complete Guide to Coordinate Distance Calculation

What This Calculator Does

This tool calculates the great-circle distance between any two points on Earth using their latitude and longitude coordinates. Unlike map-based tools that show driving distances, this gives you the straight-line "as the crow flies" distance, which is essential for air travel, navigation, and accurate geographical measurements.

Understanding the Units

  • Kilometers (km): International standard, used in most countries except the US. For converting other length measurements, you might also find our comprehensive length converter helpful.
  • Miles (mi): Primary unit in the United States and United Kingdom
  • Meters (m): For precise, shorter distances (1 km = 1000 m)
  • Nautical Miles (nmi): Used in marine and aviation navigation (1 nmi = 1.852 km). For related aviation calculations, check out our airspeed converter.

When This Conversion Is Useful

  • Travel Planning: Estimate flight distances and durations
  • Outdoor Activities: Plan hiking, cycling, or sailing routes
  • Academic Projects: Geography, geology, or environmental studies. For mapping, you might also need an angle converter for bearings.
  • Real Estate: Calculate distances between properties and landmarks
  • Logistics: Preliminary route planning for deliveries
  • Geocaching/GPS Games: Find distances between waypoints

How the Conversion Works (Simple Explanation)

Think of the Earth as a giant ball. The calculator measures the shortest path over the ball's surface between your two points, accounting for the Earth's curvature. It's like stretching a string between two points on a globe—this gives you the most direct route, not what you'd see on a flat map.

Input Usage Guidance
  • Use decimal degrees format (e.g., 40.7128 not 40°42'46"). If you have coordinates in a different format, our DMS to decimal degrees converter can help.
  • Latitude ranges from -90° (South Pole) to +90° (North Pole)
  • Longitude ranges from -180° to +180° (negative = West, positive = East)
  • The "Use Current Location" button automatically fills Point A with your coordinates
  • Swap coordinates with the middle button if you enter points backwards

Interpreting Your Results

The main result shows the distance in your selected "To" unit. The four smaller boxes display all unit conversions simultaneously, so you can instantly see kilometers, miles, meters, and nautical miles without recalculating.

Accuracy & Rounding Notes
  • Results are accurate to approximately 0.3% due to Earth's spherical approximation
  • All distances are displayed with 2 decimal places for clarity
  • The Earth's radius used is 6,371 km (mean radius)
  • For distances under 20 km, curvature effects are minimal
  • This calculates straight-line distance, not travel distance via roads

Common Mistakes to Avoid

  • Confusing latitude/longitude order: Always enter Latitude first
  • Using wrong format: Use decimal degrees, not degrees/minutes/seconds
  • Sign errors: Remember negative for West longitudes and South latitudes
  • Expecting driving distance: This is straight-line distance only
  • Forgetting hemisphere: Sydney has negative latitude (-33.8688)
  • Assuming flat Earth: Curvature matters for distances over 20 km

Practical Real-World Examples

New York to Los Angeles: 40.7128°N, 74.0060°W to 34.0522°N, 118.2437°W = ~3,941 km (2,448 miles)
London to Paris: 51.5074°N, 0.1278°W to 48.8566°N, 2.3522°E = ~344 km (214 miles)
Tokyo to Sydney: 35.6762°N, 139.6503°E to -33.8688°S, 151.2093°E = ~7,822 km (4,860 miles)

Student Learning Tips

  • Compare great-circle distances with flat-map measurements to understand Earth's curvature
  • Use the calculator to verify your manual Haversine formula calculations
  • Experiment with antipodal points (exact opposites) to see maximum possible distances
  • Notice how distance changes when you're near the poles vs. equator
  • Try calculating distances between cities on same latitude to see longitude's effect

Professional Usage Notes

  • Pilots/Navigators: Use nautical miles for aviation/marine applications. You can also explore our altitude converter for flight planning.
  • Surveyors: This is a preliminary tool; use specialized equipment for exact measurements. For related calculations, a slope gradient converter might be useful.
  • Researchers: For scientific accuracy, consider using Vincenty's formula for ellipsoidal Earth model
  • Urban Planners: Combine with terrain data for more accurate distance estimations

Accessibility Considerations

  • All form controls have proper labels for screen readers
  • High contrast color scheme meets WCAG AA standards
  • Keyboard navigation supported (Tab through fields, Enter to calculate)
  • Responsive design works on all screen sizes
  • Clear error messages for invalid coordinate inputs

Device Compatibility

This calculator works on all modern devices:

  • Desktop/Laptop: Full feature set with keyboard input
  • Tablets: Touch-friendly buttons and inputs
  • Smartphones: Optimized layout, geolocation support
  • Browsers: Chrome, Firefox, Safari, Edge (latest versions)

Frequently Asked Questions

This tool calculates the straight-line "great circle" distance (like a plane would fly), while Google Maps shows road distance following highways and streets. The straight-line distance is always shorter.
For most practical purposes, it's over 99.7% accurate. The Haversine formula assumes a perfect sphere, while Earth is slightly flattened at the poles. For precise surveying work, use specialized equipment.
Yes, but for distances under 1 km, Earth's curvature is negligible. For ultra-precise short measurements (like construction), consider using planar geometry or specialized surveying tools.
Most mapping services (Google Maps, Apple Maps) show coordinates when you right-click a location. You can also search "coordinates of [city name]" or use the built-in "Use Current Location" button for your current position.
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Tool Information

Version: 2.1 (November 2025) | Algorithm: Haversine formula | Earth Radius: 6,371 km (mean) | Updates: Regular accuracy verification against known geographical distances

Note on Calculations

This tool is designed for educational, planning, and general reference purposes. For critical applications like aviation navigation or legal surveying, consult certified professionals and use official, certified tools and data sources.