Photogrammetry Accuracy Estimate Calculator
Estimates horizontal and vertical mapping accuracy for a drone survey from ground sample distance.
Enter Values
Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.
How to use this calculator
- Enter the ground sample distance (GSD).
- Press Calculate.
- Read the rough horizontal and vertical accuracy.
How it works
A rule of thumb: horizontal accuracy ≈ 1–2× GSD and vertical accuracy ≈ 2–3× GSD, assuming good ground control and overlap.
Worked example
2 cm GSD. ≈ 2–4 cm horizontal, 4–6 cm vertical.
Frequently asked questions
How do I get better accuracy?
Lower GSD (fly lower), more overlap, good ground control points (GCPs) and an RTK/PPK drone.
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- Drone Image Count Calculator
Explore more in Surveying, Coordinates, GIS & CAD.
Cite this tool
Zerdly. (2026). Photogrammetry Accuracy Estimate Calculator. Retrieved from https://www.zerdly.com/tools/photogrammetry-accuracy-estimate-calculator/
Tip: Enter any known values to calculate the remaining results.
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