Trilateration Calculation
Calculate an unknown survey station from measured distances to known control points, with robust solution checking, residuals and optional four-point least-squares adjustment.
Three-Point Trilateration
Use three known control-point coordinates and measured distances to determine the unknown station P. The calculator checks the geometry and reports the distance residuals.
Control Point A
Control Point B
Control Point C
Solution Settings
The exact three-circle solution is obtained from the linearized squared-distance equations. Residuals are then recomputed against the original measured distances.
4+ Point Trilateration Adjustment
Enter up to six known points and measured distances. With four or more observations, the calculator performs a nonlinear least-squares coordinate adjustment and reports the residuals.
Known Points & Distances
Rows E and F are optional. Leave all three fields in an optional row blank to omit that point.
Adjustment Settings
Trilateration Formula Reference
Survey conventions and equations used by this calculator.