How do I measure an irregular lawn?

Break it into simple shapes (rectangles, triangles, circles). Calculate each section separately and add them together. Subtract any obstacles like paths or flower beds.

Why do I need to know my lawn area?

Lawn area is essential for calculating correct quantities of seed, feed, weedkiller, and top dressing. Too much or too little of any product causes problems.

How do I measure a curved lawn?

For a roughly circular lawn, measure the diameter (longest width). For a kidney shape, calculate as a circle minus cut-out areas.

How do I measure a lawn without going outside?

Use Google Maps satellite view. Zoom in, use the measure distance tool to trace the perimeter, and it will calculate the area. This gives a rough but useful estimate.

Should I subtract flower beds from my lawn area?

Yes. Subtract the area of any beds, ponds, trees, or paths within the lawn to avoid over-ordering materials like seed, feed, or turf.

GardenCalcs

Lawn Area Calculator — Measure Your Lawn

Calculate your lawn area including irregular shapes and obstacles.

Shape

Length

Width

Obstacle Areas (paths, beds)

How We Calculate This

Rectangle: Length × Width. Circle: π × (Diameter/2)². Triangle: 0.5 × Base × Height. L-shape: estimated at 75% of bounding rectangle.

Obstacle areas (flower beds, paths, sheds) are subtracted from the gross area to give the net lawn area.

Perimeter is also calculated for edging requirements.

Frequently Asked Questions

Related Calculators

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Overseeding Calculator

Calculate seed rates for patching and thickening existing lawns.

Top Dressing Calculator

Work out how much top dressing mix to level and improve your lawn.

Last updated: February 2026

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