Distance Calculator

Distance
5
straight-line distance

What Is a Distance Calculator?

This calculator finds the straight-line distance between two points — either simple (x, y) coordinates using the distance formula, or real-world latitude/longitude coordinates using the Haversine formula, which accounts for Earth's curvature.

How to Use the Distance Calculator

  1. Choose 2D points or Earth lat/long coordinates.
  2. Enter the coordinates of both points.
  3. View the calculated distance instantly.

Distance Formulas

2D Distance Formula
d = √[(x₂−x₁)² + (y₂−y₁)²]
Haversine Formula (Earth Distance)
d = 2r × arcsin(√[sin²(Δφ/2) + cos(φ₁)cos(φ₂)sin²(Δλ/2)])
r = Earth's radius (≈ 3,959 miles or 6,371 km)
φ = latitude
λ = longitude

Worked Example

Example: Points (0,0) and (3,4)

d = √[(3−0)² + (4−0)²] = √(9+16) = √25 = 5

Example: New York City to Los Angeles

NYC: 40.7128°N, 74.0060°W

LA: 34.0522°N, 118.2437°W

Great-circle distance: approximately 2,446 miles

Understanding Your Results

The 2D distance formula gives the straight-line ("as the crow flies") distance between two flat-plane points. The Haversine formula does the same for two points on Earth's curved surface, accounting for the planet's roughly spherical shape — this is why it's used for flight distances and geographic calculations.

Common Mistakes to Avoid

  • Using the simple 2D formula for real-world geographic coordinates, which ignores Earth's curvature and produces inaccurate results over long distances.
  • Mixing up latitude and longitude order when entering coordinates.
  • Forgetting that great-circle distance is a straight-line estimate, not actual driving or flight path distance.

Frequently Asked Questions

For flat (2D) coordinates, use the distance formula: √[(x₂−x₁)² + (y₂−y₁)²]. For real-world locations, use the Haversine formula, which accounts for Earth's curvature.

It calculates the great-circle (straight-line) distance between two points on Earth's surface, given their latitude and longitude — commonly used for flight distances and geographic applications.

Great-circle distance is the straight-line distance 'as the crow flies,' while driving distance follows roads and can be significantly longer due to terrain, routing, and infrastructure.

It's quite accurate for most purposes, assuming Earth as a perfect sphere. More precise methods (like Vincenty's formula) account for Earth's slight ellipsoidal shape, though the difference is typically small.

Yes — for flat 2D coordinates like a map grid or blueprint, use the standard distance formula mode.