Work out stadia distance instantly with clear inputs, formula shown and shareable results.
Tacheometry uses the staff intercept between two stadia hairs: horizontal distance is K s cos²θ + C cosθ, where K is typically 100 and C the additive constant of the telescope. The height difference uses K s cosθ sinθ, which is half K s sin 2θ. For a level sight the relation collapses to the familiar 100 times the intercept.
Stadia distance
D = K s cos²θ + C cos θ
Height difference
V = K s cos θ sin θ + C sin θ
D = K s cos²θ + C cos θ. Tacheometry uses the staff intercept between two stadia hairs: horizontal distance is K s cos²θ + C cosθ, where K is typically 100 and C the additive constant of the telescope.
About one in five hundred at best, so around 200 mm at 100 metres. It was a rapid detail survey method rather than a control technique, and total stations have made it largely historical.
This calculator takes 4 inputs: Staff intercept between stadia hairs, Multiplying constant, Additive constant, Vertical angle. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.