HomeCalculatorsRadar & Optical Horizon

Radar & Optical Horizon

Horizon distance - how far a radar or an observer can see - as a function of antenna/eye height.

NavigationRadar
Radar horizon
11.2nm
Optical horizon
10.4nm
Formula, assumptions, and limits

Empirical formulae with refraction factor k = 4/3 for radar and k = 7/6 for visible light. Target detection range is the sum of own-ship horizon and target-height horizon.

Symbol legend

SymbolMeaningUnitSource
Height above sea levelmship layout
Horizon distancenmresult