How to Use the Haversine Formula to Calculate GPS Distance in JavaScript

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Calculating real-world distance between two GPS coordinates requires accounting for Earth's curvature, as simple arithmetic on latitude and longitude values produces meaningless results. The Haversine formula offers a practical solution by computing the great-circle distance between two points on a sphere using their coordinates. A JavaScript implementation involves converting degrees to radians, applying trigonometric functions, and multiplying the resulting central angle by Earth's radius. The approach supports output in kilometers, miles, and nautical miles, and can be extended with input validation and TypeScript support. As a practical example, the formula returns approximately 3,935 km between New York City and Los Angeles.

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