Lawn Area Calculator
Calculate the area of a lawn and the mowing and watering it will need.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
About this calculator
Lawns are rarely simple rectangles, so the most accurate approach is to divide the space into shapes, measure each and add them up. Most lawn products are dosed per thousand square feet, which makes the total area the key number. For an L-shape, enter two non-overlapping rectangles so the shared area is not counted twice.
Worked example
calculated with the default values below
Shape Rectangle · Length or diameter 50 ft · Width or second length 30 ft · Extra length (L-shape) 20 ft · Extra width (L-shape) 10 ft Lawn area 1,500.0 sq ft · Lawn area 139.35 m² · Units of 1,000 sq ft 1.500
Method and assumptions
A = {L×W rectangle; π×(L÷2)² circle; L×W÷2 triangle; L×W + L₂×W₂ for two non-overlapping L-shape sections} L-shape area is the sum of two non-overlapping rectangles. No mowing-time or watering estimate is returned. Lawns are rarely simple rectangles, so the most accurate approach is to divide the space into shapes, measure each and add them up. Most lawn products are dosed per thousand square feet, which makes the total area the key number. For an L-shape, enter two non-overlapping rectangles so the shared area is not counted twice. Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
Data sources
Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
Disclaimer
These are general gardening estimates. Planting windows, growth, water and nutrient needs vary by place and plant. Check local extension guidance and product labels before acting on an estimate.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
A = {L×W rectangle; π×(L÷2)² circle; L×W÷2 triangle; L×W + L₂×W₂ for two non-overlapping L-shape sections}
- A
- Lawn area
- s
- Shape code: rect, circ, tri, L
- L
- Length
- W
- Width
- L₂
- Second section length
- W₂
- Second section width
L-shape area is the sum of two non-overlapping rectangles. No mowing-time or watering estimate is returned.
Frequently asked questions
How is an L-shaped lawn measured?
Enter the L as two non-overlapping rectangles and add their areas. If the rectangles overlap, the shared area would be counted twice. The calculator reports area only; watering and mowing needs depend on local and site conditions.
Which inputs and limits apply to Lawn Area Calculator?
Use the units shown beside each field. These are form limits, not recommended settings. Length or diameter: 0.1–5,000 ft; Width or second length: 0.1–5,000 ft; Extra length (L-shape): 0–5,000 ft; Extra width (L-shape): 0–5,000 ft A = {L×W rectangle; π×(L÷2)² circle; L×W÷2 triangle; L×W + L₂×W₂ for two non-overlapping L-shape sections} L-shape area is the sum of two non-overlapping rectangles. No mowing-time or watering estimate is returned. Lawns are rarely simple rectangles, so the most accurate approach is to divide the space into shapes, measure each and add them up. Most lawn products are dosed per thousand square feet, which makes the total area the key number. For an L-shape, enter two non-overlapping rectangles so the shared area is not counted twice. Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
What is a complete worked example for Shape = Rectangle; Length or diameter = 50 ft?
Inputs: Shape = Rectangle; Length or diameter = 50 ft; Width or second length = 30 ft; Extra length (L-shape) = 20 ft; Extra width (L-shape) = 10 ft. Calculation: A = {L×W rectangle; π×(L÷2)² circle; L×W÷2 triangle; L×W + L₂×W₂ for two non-overlapping L-shape sections}. Results: Lawn area = 1,500.0 sq ft; Lawn area = 139.35 m²; Units of 1,000 sq ft = 1.500.