Topsoil Calculator
Work out how much topsoil you need for a garden bed or lawn — in cubic metres, cubic yards, tonnes and bags — from its length, width and fill depth.
m
m
Area units
cm
Depth units
L
Price basis
Loose volume needed to fill the bed
1.5 m³
- 1
Depth in metres
10 ÷ 100 = 0.1 - 2
Volume (m³)
5 × 3 × 0.1 = 1.500
How does this calculator work?
To find how much topsoil you need, multiply the bed length × width × fill depth in metres for the volume in cubic metres. Multiply that by 1.3 for weight in tonnes, by 1.308 for cubic yards, and divide by your bag volume (25 L = 0.025 m³) and round up for bag count. Order around 10% extra.
Formula
How this is calculated
Enter the length and width of the area you want to cover and choose whether those measurements are in metres or feet. Feet are converted to metres (1 ft = 0.3048 m) before any maths. Pick a fill depth in centimetres or inches; this is converted to metres (1 cm = 0.01 m, 1 in = 0.0254 m). Multiplying length × width × depth gives the loose volume of topsoil required in cubic metres.
The volume is then converted to other common units. Cubic yards = m³ × 1.308, and weight in tonnes = m³ × 1.3, using a typical screened-topsoil bulk density of about 1.3 tonnes per cubic metre. Bag count divides the total volume by the bag volume (bag litres ÷ 1000, defaulting to 25 L = 0.025 m³) and rounds up, since you cannot buy a partial bag.
Cost is estimated either as tonnes × price-per-tonne or bags × price-per-bag depending on the price basis you select. Real topsoil density varies with moisture and organic content (roughly 1.1–1.6 t/m³), and settling or compaction can change how far a load goes, so treat the figures as planning estimates and order a little extra.
Frequently asked questions
Typical screened topsoil weighs about 1.3 tonnes per cubic metre, though this ranges from roughly 1.1 to 1.6 tonnes depending on moisture and how much sand, clay or organic matter it contains.
For a new lawn aim for about 10–15 cm of topsoil, while flower or vegetable beds often want 20–30 cm. Use the depth field to match your project and the calculator updates the volume and bag count.
Yes. Soil settles and compacts after delivery and ground is rarely perfectly level, so ordering 5–10% more than the calculated volume helps you avoid running short.
Also known as
TG we-Calculate Editorial Team. (2026). Topsoil Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/topsoil-calculator
TG we-Calculate Editorial Team. "Topsoil Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/topsoil-calculator.
TG we-Calculate Editorial Team, "Topsoil Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/topsoil-calculator
@misc{wecalculate_topsoil_calculator, title = {Topsoil Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/topsoil-calculator}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?