🛫 Flight Distance Calculator
Pick two cities (or enter coordinates) to get the great-circle distance, the compass bearing between them, and a rough flight time — drawn on a world map.
From
To
Great-circle distance
5,540 km
3,442 mi · 2,991 nm
Initial bearing
51° NE
Rough flight time
7 h 10 m
This is the great-circle (straight-line) distance — the shortest path over a spherical Earth (mean radius 6,371 km). Real flights are longer because of airways, air-traffic routing and winds, so the flight time (distance ÷ ~830 km/h cruise + ~30 min for taxi/climb/descent) is a rough estimate only. 🔒 In your browser.
How the flight distance calculator works
The shortest distance between two points on the globe follows a great circle. From each place's latitude and longitude the tool applies the haversine formula on a spherical Earth (mean radius 6,371 km) to get the distance, and computes the initial compass bearing you'd set off on. It also estimates a rough flight time — distance divided by a typical jetliner cruise speed (~830 km/h) plus about 30 minutes for taxi, climb, descent and approach.
This is the great-circle (straight-line) distance — the theoretical shortest path. Actual flights are longer because they follow airways, avoid restricted airspace and ride the winds, and the flight-time figure is an approximation that ignores head- and tail-winds. Use it for planning and comparison, not exact scheduling.
Frequently asked questions
How is flight distance calculated?
By the great-circle distance — the shortest path over a spherical Earth — using the haversine formula on the two points' latitude and longitude with a mean Earth radius of 6,371 km. It's the same method aviation and mapping tools use for straight-line distance.
Why is the actual flight longer than this distance?
Aircraft follow published airways and air-traffic routing, detour around restricted or weather-affected airspace, and route to catch tailwinds or avoid headwinds. The great-circle distance is the shortest possible path, so real routes are a bit longer.
What is a great-circle distance?
The shortest distance between two points on a sphere, measured along the circle whose centre is the centre of the Earth. On a flat map it looks curved, which is why long flights appear to arc toward the poles.
How accurate is the distance?
The haversine formula assumes a perfect sphere, so it's within about 0.5% of the true (ellipsoidal) distance — plenty accurate for travel planning. For survey-grade geodesy you'd use the Vincenty or Karney method on the WGS-84 ellipsoid.
What is the bearing?
The initial compass direction (0° = north, 90° = east) you'd head to follow the great circle. On a long route the bearing changes along the way, which is why it's labelled the "initial" bearing.