Notes on this calculator
This depth of field calculator will give you the aperture needed to achieve a specific depth of field if you know the height of an object.
Some more uses for this calculator
It can also help you determine the distance at which you should be from the object to fill the frame. For example if you want to know how far you need to be from a building of 50m (5000cm) height, you simply input it with your desired focal length.
If you want the subject to cover only part of the frame, you can multiply the height by the percentage of coverage.
Do you want more calculators?
Here is a link to a list of photo calculators.