ControlPoint

Least-squares survey network adjustment — in the browser — TPS, levelling, tape and GNSS. Your data never leaves your device.
Manual

Modules

TPSlive Total-station network adjustment — 2D and 3D least squares, error ellipses, traverses, resections and free stations; Leica DBX import; StarNet-compatible .dat and .lst import. Open
Levellinglive Differential levelling adjustment — GSI, LandXML and .dat fieldbooks; benchmark holds; 1D least squares; .lst import. Open
Best Fitlive Coordinate transformation — weighted similarity fits (2D, 2D + heights, 3D); match by name, geometry or by hand. Open
Tape Droplive Tape corrections and levelling fieldbook — installable as a phone app. Open
GNSSbeta Baseline processing and vector networks — engine validated against published ITRF2020 and independent processing; interface in progress. Info

Network plot

CP01CP02CP03CP04ST03ST04ST05ST06ST07ST08ST09ST10
Braced control network — 12 stations, 26 measured legs, 112 observations. Triangles = held control; circles = adjusted stations with error ellipses.

Method

Rigorous least-squares adjustment · a-priori standard errors and centring · σ̂₀ and chi-square test · error ellipses and relative confidences · traverses, resections and free stations · benchmark and datum holds · StarNet-compatible .dat and .lst import · CPOBS observation files · CSV, points and DXF export
🔒 Zero-egress — computation runs entirely in your browser (WebAssembly); nothing is installed and nothing is uploaded. Verified against 150+ real adjustments from existing archives, agreement ≤0.1 mm. Independently validated · access-controlled.