Irregular Plot Area Calculator
Calculate an irregular polygon area from ordered X,Y boundary points. The tool also shows perimeter and bounding-box dimensions as quick input checks.
Boundary coordinates
Enter one coordinate pair per line in boundary order, for example 0,0.
Shoelace area method
For a simple, non-self-intersecting polygon, the shoelace formula converts ordered planar coordinates into area. The calculator automatically closes the final edge back to the first point.
Why point order matters
The coordinates should trace the actual boundary continuously. A scrambled list can return a number that does not represent the intended plot.
Useful input check
Perimeter and bounding-box dimensions are shown alongside the area so obvious coordinate mistakes are easier to notice.
Frequently Asked Questions
Can coordinates be negative?
Yes.
Does this accept latitude and longitude?
No. Use planar project coordinates.
What if the boundary crosses itself?
The result should not be treated as a normal site-area calculation for a self-intersecting boundary.