Plot Area Calculator Nepal: Land Area from Sides in Ropani, Aana and Kattha

Plot Area Calculator (from site measurements)

Find land area from side lengths or survey coordinates, in sq ft, m², Ropani and Bigha.

Measured in

Side AB

Side BC

Side CD

Side DA

Diagonal AC

Side a

Side b

Side c

Length

Width

Corner coordinates, one point per line as X, Y (Easting, Northing) in order around the plot

Free tool by EngineeringNepal.com.np · Results are for guidance; check critical figures with a qualified engineer.

Finding land area from tape measurements

Most plots in Nepal are not perfect rectangles, so multiplying length by width gives the wrong area. The reliable way on site is to measure all four sides and one diagonal with a tape. The diagonal splits the plot into two triangles, and the area of each triangle comes from its three sides using Heron's formula. This calculator does that and shows the result in square feet, square metres, ropani-aana-paisa-daam and bigha-kattha-dhur.

How to measure your plot

Name the corners A, B, C and D going around the plot.
Measure the four sides AB, BC, CD and DA along the boundary.
Measure one diagonal, from corner A to corner C, in a straight line.
Enter the values and pick the unit you measured in: feet, metres or haat.

If you have corner coordinates from a total station or GPS survey, use the Coordinates tab. Enter points in order around the boundary (clockwise or anti-clockwise), and the shoelace method gives the enclosed area.

Formulas used

Heron's formula: for a triangle with sides a, b and c, s = (a + b + c) / 2 and Area = √[s(s − a)(s − b)(s − c)].

Shoelace formula: Area = ½ |Σ (x_i·y_i+1 − x_i+1·y_i)| over all corners.

Frequently asked questions

Why does my measured area differ from the lalpurja?

Small differences are common because of old survey methods, tape sag, boundary walls and rounding. A large difference should be checked with a licensed surveyor and the Survey Office (Napi Karyalaya) map.