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Calculate Field of View

Use the following form to calculate the horizontal and vertical field of view (a rectangular plane) you get with a lens at a specific distance. Input the distance, input your lens size, and click CALCULATE.


1. The area in FIELD OF VIEW is not necessarily in focus.

2. A fixed-focus lens has a pre-set distance at which objects are in focus. For a 3.6mm fixed-focus lens that distance is generally 5-20' from the lens. Objects closer or further than the pre-set focus distance will be out of focus in proportion to the amount of distance they are inside/outside of that zone. For flexible focus control use a camera with a varifocal lens.


Field of View Calculator

(input) Distance to Target : ft
(input) Lens Size : mm
(result) Field of view (H x V): horizontal feet x vertical feet








Useage Advisory

This page is provided as a convenient tool for selecting lenses. Due to the large number of unpredictable factors in every surveillance environment, the calculation can not be assumed to be exact. Use caution when selecting a lens. We suggest that you always purchase a lens with a greater field of view than this calculation indicates. 

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