Tree Height Calculator (Clinometer Method)
The height of a tree, pole or building from your distance to it, the angle up to its top and your eye height.
Results
The dashed line marks the value you entered.
What this tool does
Stand a measured distance from the tree on level ground, sight the top with a clinometer (a phone app works) and read the angle: height = distance × tan(angle) + eye height. The eye-height term is easy to forget, since the angle is measured from your eye, not the ground. A handy shortcut: walk back until the top appears at exactly 45°, and the height is then your distance plus your eye height. Accuracy falls as the angle grows — a 1° error at 45° is a 3.5 % error in the height above the eye — so choose a spot about as far from the tree as it is tall, and on a slope or with a leaning trunk measure the angle to the base as well.
Formula
height = d × tan θ + eye height · line of sight = d ÷ cos θ
Variables
| Symbol | Meaning | Unit |
|---|---|---|
dd | Horizontal distance to the tree | m |
an | Angle up to the top of the tree (clinometer) | ° |
ey | Height of your eye above the ground | m |
HT | Height of the tree | m |
HE | Part of the height above your eye | m |
LS | Distance along the line of sight to the top | m |
Worked example
- Horizontal distance to the tree20 m
- Angle up to the top of the tree (clinometer)35 °
- Height of your eye above the ground1.6 m
- Height of the tree15.6 m
- Part of the height above your eye14.0 m
- Distance along the line of sight to the top24.4 m
Limitations
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.