Drone GSD Calculator

Ground sample distance · flight altitude · image footprint · flight plan — free, instant, private

1 Ground Sample Distance & Flight Altitude
Pick your drone, enter flight altitude to get GSD — or enter the GSD your project requires to get the altitude you should fly.
m
cm/px
GSD at Current Altitude
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Single Image Footprint
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Coverage per Image
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Required Altitude for Target GSD
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2 Flight Plan Estimator
Overlap and survey area details. Defaults follow industry-standard 80% forward / 70% side overlap.
%
%
m long
m wide
m/s
Total Photos
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Flight Line Spacing
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Photo Interval
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Flight Lines × Photos/Line
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Flight Distance / Time
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3 GSD Reference Table
GSD and single-image footprint for every preset, at 100 m (328 ft) above ground.
Drone / CameraGSD @100 mFootprint @100 mCoverage

What is GSD (Ground Sample Distance)?

Ground Sample Distance is the real-world size of a single pixel in your aerial photo. A GSD of 3 cm/px means one pixel represents a 3 cm × 3 cm square on the ground. It is the single most important number in drone mapping: it sets the resolution of your orthomosaic, point cloud, and 3D model, and it is usually the first requirement written into a survey contract (“deliverables at 3 cm/pixel”).

GSD depends on three things: your flight altitude, the camera’s focal length, and the camera’s sensor resolution and size. Fly higher and GSD gets coarser; use a longer lens or a higher-resolution sensor and GSD gets finer. This drone GSD calculator combines all three instantly, with manufacturer presets for the most common mapping aircraft.

How the Drone GSD Calculator Works

The formula behind every GSD calculator is the same geometry used in photogrammetry software like DJI Terra and Pix4D:

GSD = (sensor width / image width in pixels) × (flight altitude / focal length)

All dimensions must be in consistent units. For example, a 1-inch sensor (13.2 mm wide) with an 8.8 mm lens capturing 5472-pixel-wide images at 100 m altitude gives a GSD of 2.74 cm/px — matching DJI’s published figure of H/36.5 for the Phantom 4 RTK. The calculator also works the formula backwards: enter the GSD your client asks for and it tells you the maximum altitude you may fly.

Choosing Flight Altitude and Target GSD

Common mapping deliverables call for 1-2 cm/px on tight engineering or stockpile surveys, 3-5 cm/px for general topographic and construction mapping, and 5-10 cm/px for large-area progress monitoring and agriculture. Finer GSD means lower altitude, more images, longer flights, and heavier processing — so always plan at the coarsest GSD that still meets the spec.

Remember that GSD changes with terrain: if your survey area has hills or tall structures, the distance from camera to ground varies, and so does the actual GSD. Plan to the highest terrain point, or use terrain-following flight modes. Also note that GSD is not the same as survey accuracy — with RTK positioning or ground control points, horizontal accuracy typically reaches 1-2× GSD; without them it can be several times worse.

Image Footprint, Overlap and Flight Planning

Each nadir photo covers a rectangular patch of ground: the footprint width is simply GSD × image width, and footprint length is GSD × image height. Adjacent images must overlap so photogrammetry software can match features between them. The industry standard — and DJI Terra / Pix4D default — is 80% forward overlap (between successive photos on a line) and 70% side overlap (between parallel flight lines). Increase to 85/80 for dense vegetation, steep terrain, or 3D modeling work.

The flight plan estimator above converts overlap into actionable settings: the spacing between flight lines, the distance (and at your cruise speed, the time interval) between photos, the number of lines and photos for a rectangular survey area, and total flight distance including an allowance for turns. If the required photo interval drops below about 0.7 seconds — the fastest interval of mapping cameras like the Phantom 4 RTK, Mavic 3E, and Zenmuse P1 — you must fly slower or fly higher.

Supported Drones and Data Sources

Presets include the DJI Phantom 4 RTK / Phantom 4 Pro, Mavic 3 Enterprise (M3E), Mavic Air 2S, Mini 4 Pro / Mini 3 Pro (12 MP mapping mode), and the Zenmuse P1 full-frame payload with its 24/35/50 mm lenses on the Matrice 300/350 RTK. Sensor dimensions, focal lengths, and pixel counts come from official manufacturer specifications, and results are cross-checked against DJI’s published GSD figures (for example H/36.5 for the Phantom 4 RTK and H/37 for the Mavic 3E). Flying a fixed-wing or another custom rig? Choose Custom camera and enter your own sensor width, focal length, and image dimensions. Consumer drones with rolling shutters (Air 2S, Mini series) can produce usable orthomosaics at moderate flight speeds, but mechanical-shutter mapping aircraft remain the professional standard for survey-grade work.