RHC ENGINEERING

Free engineering tools
Surveying

Lot Plotter — Plot Lot Boundaries from Bearings and Distances

Plot a property's metes-and-bounds in seconds, get a ready-to-print lot diagram, and compute area by the surveyor's (shoelace) formula — without firing up AutoCAD.

Formulas

QuantityFormula
Latitude (Y component) of a courseLat = D · cos(B)
Departure (X component) of a courseDep = D · sin(B)
Surveyor's (shoelace) areaA = ½ |Σ (x_i · y_{i+1} − x_{i+1} · y_i)|
Linear closure errorC = √(ΣLat² + ΣDep²)

How to use it

  1. Enter starting tie point or accept the default (0, 0).
  2. For each course, enter bearing as N 12°34′56″ E (DMS) or +123.5829° (decimal) and the distance in metres.
  3. Add courses until the lot closes. The plotter draws the polygon as you add each line.
  4. Read the area in square metres and hectares, plus the linear closure error.
  5. Export the diagram as SVG/PNG for your transmittal.

Frequently Asked Questions

How is bearing direction interpreted?

Bearings follow the standard surveyor's quadrant convention (N __ E, N __ W, S __ E, S __ W). If you have azimuths, convert first: bearing = azimuth − 0/180/360 depending on quadrant.

What's an acceptable closure error?

Cadastral surveys in the Philippines target 1:5000 to 1:10000 (i.e., closure error ≤ perimeter / 5000). Construction layouts often accept 1:2500.

Does it handle curved boundaries?

Not yet. Curves can be approximated by chords. A future release will support arc segments.

Can I import a CSV of bearings and distances?

Yes — paste a bearings/distances table directly into the input area.

Try it now

The Lot Plotter — Bearings, Distances, and Area Calculator runs entirely in your browser. No signup, no installation.

Open the Lot Plotter