Angle of Depression Calculator

Enter a height and horizontal distance to calculate the angle of depression.

How to Use the Angle of Depression Calculator

Enter the height dropped and the horizontal distance to the object. The angle of depression comes out below.

angle of depression = tan⁻¹(height ÷ horizontal distance)

The angle of depression is measured downward from a horizontal line at the observer's eye level — someone standing on a cliff looking down at a boat, say. It's easy to confuse with the angle at the boat looking up, but the two are always identical: the horizontal sightline and the ground below it are parallel, so alternate interior angles make the depression angle at the top exactly equal to the elevation angle at the bottom.

That equivalence is why this calculator and the Angle of Elevation Calculator share the same formula — the difference is entirely in which end of the sightline is doing the measuring.