How do I calculate the area of an irregular garden?

Break the space into regular shapes (rectangles, triangles, circles), calculate each area separately, then add them together for the total.

What is a square metre?

A square metre (m²) is a metric unit of area equal to a square with sides of 1 metre. It is the standard unit for measuring garden areas in the UK.

How do I convert square metres to square feet?

Multiply square metres by 10.764 to get square feet. For example, 50 m² is approximately 538 sq ft.

Why do I need to know my garden area?

Knowing your garden area helps you buy the correct amount of turf, seed, gravel, paving, mulch, or other materials without over- or under-ordering.

How do I measure a triangular garden area?

Measure the base and the height (perpendicular distance from base to opposite corner). Area = base x height / 2. For irregular triangles, use all three sides with Heron's formula.

GardenCalcs

Area Calculator — Garden Area in Square Metres

Calculate the area of rectangular, circular, and triangular garden spaces.

Shape

Length

Width

How We Calculate This

Rectangle: Area = Length x Width. Circle: Area = pi x Radius². Triangle: Area = 0.5 x Base x Height.

Semi-circle: Area = 0.5 x pi x Radius². L-shape: split into two rectangles and add them together.

All measurements are in metres, and results are given in square metres (m²).

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.