Lawn Area Calculator
Measure an irregular lawn by summing rectangles, triangles, circles, semicircles and ovals — subtract beds, drives, and pools — into one total in sq ft, sq yd, acres, and m². No map or login.
How this is calculated
Enter each piece of your lawn as a simple shape, tag it add (lawn) or subtract (a bed, driveway, patio, or pool), and we sum them into one net total. The four-unit line is computed from the unrounded net, so the number drops straight into per-1,000-sq-ft or per-acre product math.
rectangle = l × w
triangle = (base × height) / 2
circle = π × r² (π = 3.14159)
semicircle = (π × r²) / 2
oval = l × w × 0.8 (Clemson homeowner factor)
curved-area helpers:
offset (strip) = mean(widths) × run length
average-radius = π × mean(radii)²
aggregate:
added = Σ area where op = add
subtracted = Σ area where op = subtract
net = max(0, added − subtracted)
conversions (from the unrounded net):
sq yd = net / 9
acres = net / 43,560
m² = net / 10.7639
Primitive and curve formulas follow Clemson HGIC's Measuring the Area
of a Home Lawn; the multi-shape sum with cut-out subtraction follows
Sod Solutions. Clemson prints π as 3.14 (a homeowner rounding) — we use the
more precise 3.14159, which still reproduces the cited totals at whole
square feet. The 0.8 oval factor is Clemson's homeowner approximation, not
the exact ellipse. 1 acre = 43,560 sq ft is the standard US
unit definition. No address, map, or satellite image is used.
Sources
- Measuring the Area of a Home Lawn. Clemson Cooperative Extension (HGIC). Retrieved .
- Area Calculator (multi-shape with cut-outs). Sod Solutions. Retrieved .
- Lawn Size Calculator. LawnEsto. Retrieved .