Distance Calculator

How Distance is Calculated

This tool uses the Haversine formula to calculate the great-circle distance between two points on the Earth's surface. This is the shortest distance over the earth's surface, giving an "as the crow flies" measurement.

Because the Earth is a sphere (or closely approximated as one), calculating the straight-line distance requires spherical trigonometry. The Haversine formula accounts for the curvature of the Earth, providing an accurate measure of distance between any two global coordinates.

Driving Time Estimates

The estimated driving time provided is based on the straight-line (great-circle) distance and a default average speed (which you can adjust). Please keep the following in mind:

• Straight-Line vs. Road Distance: Roads rarely go in a perfectly straight line. Actual driving distances are typically 15% to 30% longer than the straight-line distance, depending on geography and road infrastructure.
• Speed Variability: The default speed assumes highway driving. Your actual average speed will be lower due to traffic, rest stops, city driving, and speed limits.
• No Routing Data: Since this tool works entirely offline and client-side, it does not use routing APIs (like Google Maps) to determine actual roads, ferries, or natural obstacles like oceans and mountains.

Why Use an Offline Distance Calculator?

Whether you're planning a trip while on a flight with no Wi-Fi, plotting coordinates in a remote location, or simply need a fast, privacy-respecting tool that doesn't send your data to third-party servers, an offline calculator is invaluable. By processing all calculations directly in your browser using JavaScript, your location data never leaves your device.