JoseFitani
🌍 Earth Measurement

Bearing Calculator

Calculate the initial and final compass bearing between two points.

This page explains how the bearing calculator works, the data and formulas behind it, and how to interpret the result. Great-circle distances are the shortest path over the Earth's surface - the route aeroplanes actually follow. They are the baseline every other distance estimate starts from, and are accurate to ~0.3% of the more complex ellipsoidal (WGS84) distance. The tool is one of 329 free, open tools on JoseFitani for maps and geography. It runs in your browser with no sign-up needed. Use the search field or click the map to drop a pin - the tool uses the Haversine formula on a sphere of radius 6,371 km, plus mode-specific detour factors for driving, walking and flight-time estimates and returns the result in seconds. Below you'll find a step-by-step guide, real use cases, the methodology, FAQs, and data sources.

Initial bearing
288.3°
clockwise from true north
Compass point
WNW

Formula: initial bearing from spherical trigonometry on the WGS84 mean radius. This is the direction to set off in; on long routes the bearing changes as you follow the great circle.

How to use this tool

1
Enter your input

Type your query, paste coordinates, or click on the map. The tool uses the Haversine formula on a sphere of radius 6,371 km, plus mode-specific detour factors for driving, walking and flight-time estimates to process your input locally in the browser.

2
View the result

The result appears instantly with the map showing your location. You can adjust by clicking elsewhere or searching a new place.

3
Copy or share

Click Copy to save to clipboard, or Share to send a direct link with the exact inputs.

What people use this tool for

Sailing and aviation navigation

Navigators use the initial bearing as the compass course to steer when departing toward a distant waypoint. Because the bearing changes along a great-circle route, the final bearing tells them the course they will be steering as they arrive. Comparing the two shows how much the heading swings on long ocean or air crossings.

Example: A yacht skipper sailing from the Canaries to Barbados notes the initial bearing for departure and the final bearing to anticipate the course change near landfall.
Aligning directional antennas

Anyone pointing a directional antenna — satellite dish, point-to-point Wi-Fi, amateur radio beam — needs the true bearing from their site to the target. A degree or two of error at long range means missing the target entirely, so a computed bearing beats a map eyeball. The final bearing also helps when aligning the far end back toward you.

Example: An installer aligns a rural broadband dish by computing the bearing from the farmhouse to the provider's hilltop mast before climbing the roof.
Planning drone survey lines

Drone operators flying mapping missions need precise headings between waypoints so flight lines stay parallel and overlap stays consistent. The initial bearing gives the outbound leg heading and the final bearing the return leg. Feeding both into mission-planning software keeps the survey grid tight.

Example: A surveyor maps a quarry by computing bearings between grid corners so each drone pass runs exactly parallel to the last.
Orienting solar panels and structures

Installers positioning solar arrays, sundials, or building faces toward a specific distant feature need the true bearing from site to target. True north from this tool avoids the several-degree error of an uncorrected magnetic compass. Even small orientation errors cost measurable energy yield over a panel's lifetime.

Example: A solar installer computes the bearing from a farmhouse roof to true south to verify the proposed panel azimuth before mounting rails.

How it's calculated

Initial bearing is the heading at the start. Final bearing differs from initial on long distances due to Earth's curvature.

The calculation runs in your browser - no data is sent to our servers. Map tiles come from OpenStreetMap (ODbL license), geocoding uses Nominatim (1 request/second limit), and elevation uses the Open-Elevation API backed by SRTM data. All are free, open services.

All calculations use the WGS84 datum (EPSG:4326), the same as GPS. For other datums (NAD27, NAD83, ETRS89), a separate conversion is needed. The difference is typically under 1 metre - negligible for most uses but important for survey-grade work.

The formulas match those in professional GIS software (QGIS, ArcGIS, Global Mapper), just in a browser-friendly form. For sub-metre accuracy, use professional software with ellipsoidal calculations. Results are shown in multiple units: km and miles for distance, km²/m²/hectares/acres for area, metres and feet for elevation. Conversion factors are exact (1 mile = 1.609344 km), so the only error source is input precision.

Related tools and resources

For more tools in this category, explore the related tools listed below. Each tool includes full documentation, examples and FAQs. Explore related tools in our Earth category for complementary functionality. See the Tools index for all 329 tools, or read our blog for in-depth articles on geography and maps.

Frequently asked questions

Why do initial and final bearing differ?

Because great-circle routes curve on a flat map.

What is the difference between initial and final bearing?

The initial bearing is the compass heading you start out on when leaving point A for point B along the shortest path. The final bearing is the heading you are on when you arrive at B. On a flat map they would be simple opposites, but on a sphere the great-circle path curves, so the two bearings differ — sometimes by many degrees on long routes.

Are these bearings relative to true north or magnetic north?

The tool computes bearings relative to true north, the geographic North Pole. A magnetic compass points to magnetic north, which sits hundreds of kilometres away and drifts over time. Apply your local magnetic variation to convert a true bearing into a compass heading before steering by it.

How are bearings expressed — degrees from which direction?

Bearings use the standard compass convention: degrees clockwise from true north, so north is 0° (or 360°), east is 90°, south is 180°, and west is 270°. This matches aviation, marine, and surveying practice. If you work in mils or grads, convert from degrees afterwards.

Why does my bearing change along the route?

Because the shortest path on a sphere is a great circle, which is not a straight line on most flat maps. To stay on it you must continuously adjust your heading, which is why long-haul flights arc toward the poles. The initial and final bearings are just the two endpoints of that gradual swing.

Can I use this for short distances like across a field?

Yes, though for short distances the initial and final bearings are nearly identical since the Earth's curvature barely matters. A handheld compass or a phone is usually more practical at that scale. The tool is most valuable where curvature actually bends the path — tens of kilometres and up.

What is a rhumb line, and is this tool one?

A rhumb line is a path of constant bearing — you steer one heading the whole way — which is longer than the great-circle route. This tool computes great-circle bearings, which change along the route but give the shortest distance. Sailors historically used rhumb lines for simplicity; modern navigation follows great circles.

How precise are the results?

The math is precise to a small fraction of a degree given accurate input coordinates. Real-world steering precision is limited by your compass, GPS, and the accuracy of the coordinates you entered. Double-check coordinate entry — a typo in a decimal degree can swing the bearing wildly.

Does this work near the poles?

Bearing math becomes unstable very close to the poles because all directions converge there. Results within a degree or two of a pole should be treated with caution. Polar navigation uses grid navigation techniques rather than plain true bearings for exactly this reason.

Data sources & methodology