Garden Area Calculator: Square Feet, m², Acres
Almost every garden calculation starts with area: seed, fertiliser, mulch, sod. Real gardens are rarely a single rectangle, so the trick is to split them into simple shapes and add them up.
Runs in your browser. Nothing you enter is stored.
What this calculator does
Enter up to three sections as rectangles, circles, triangles or ovals. The calculator adds them up and converts the total into square metres, square feet, square yards, acres or hectares.
How to use the garden area calculator
- Sketch your garden and split it into simple shapes.
- For each section choose a shape and enter its measurements.
- Set unused sections to Not used.
- Read the total area and conversions.
- Use the total in our other calculators, such as grass seed or fertiliser.
How the calculation works
rectangle = length × width circle = π × diameter² ÷ 4 triangle = base × height ÷ 2 oval = π × length × width ÷ 4 total = sum of sections
Splitting an irregular area into simple shapes is the standard way to measure gardens. Small gaps and overlaps rarely matter for buying materials.
Worked example
A 10 × 5 m lawn (50 m²), a 3 m round bed (7.07 m²) and a triangular corner with a 4 m base and 3 m height (6 m²) add up to 63.07 m², about 679 sq ft.
Assumptions and limitations
- Measure in straight lines along the ground; slopes add a little extra area.
- For very irregular shapes, take more sections or measure offsets from a baseline.
- Subtract buildings or patios by measuring them as separate sections if needed.
Frequently asked questions
How do I calculate the area of an irregular garden?
Split it into rectangles, triangles and circles, work out each area and add them together.
How many square feet are in an acre?
43,560 square feet, or about 4,047 square metres.
How do I convert square metres to square feet?
Multiply square metres by 10.764.
How do I measure a curved garden bed?
Treat it as part of a circle or oval, or split it into several smaller straight-edged sections.