Required focal length

The online calculator for the required focal length of the lens calculates its angle of view and at the same time the degree of magnification of the object at a given shooting point. Wide-angle lenses have short focal lengths, while telephoto lenses have significant focal lengths.

Note: the calculator assumes that the maximum size of the shooting object matches the maximum side of the camera frame.
The calculator is not intended for use in extreme macro photography, however takes into account small changes in the angle of view in connection with focal length.