About the garden area calculator
Before you buy soil, mulch, or plants, it helps to know exactly how much growing space you have. This calculator adds up beds of different shapes and subtracts paths, patios, and features.
Once you have the total, use it in the soil, mulch, compost, or plant spacing calculators.
How to use this calculator
- List each bed and pick the closest shape.
- Enter its dimensions in feet, yards, or meters.
- Subtract paths, stepping-stone areas, or features inside a bed.
- Copy the total for your next calculation.
Worked examples
- Round bed, 8 ft across: π × 4² = 50.3 sq ft
- Border 20 × 3 ft = 60 sq ft
About 110 sq ft of planting area.
Measurement guidance
Measure the planted area only
Measure inside edging or borders. Including the edging slightly overstates the soil and mulch you need.
Round beds
Measure straight across through the center for the diameter. If you have a stake at the center, measure the radius and double it.
Frequently asked questions
How do I calculate the area of a round bed?
Measure the diameter, halve it, square that number, and multiply by π (about 3.14).
What if my bed has a curved edge?
Approximate it with a trapezoid or combine a rectangle with part of a circle.
Can I get the answer in square meters?
Yes. Switch to metric or read the square meters line in the results.