When you need this calculation
Preparing ground for a new lawn or sod, filling low spots, building up a garden bed, or ordering a truckload of soil. Bulk soil is sold by the cubic yard in the US and the cubic meter elsewhere, and bagged soil by the cubic foot or liter.
How the volume is worked out
Area times depth gives the volume. With length and width in feet and depth in inches, divide the depth by 12 first so all three are in feet. Cubic feet divided by 27 gives cubic yards. In metric, use meters for length and width and divide the depth in centimeters by 100.
How much depth you need
- New lawn: Penn State Extension recommends at least 4 to 6 inches of good topsoil, settled.
- Topdressing an existing lawn: a thin layer, often well under an inch, so the grass isn’t smothered.
- Raised beds: use the raised bed soil calculator, which handles several beds at once.
Common mistakes
Measuring loose depth. The recommended depth is the settled depth. Freshly spread soil sits higher at first.
Ignoring slopes and hollows. For an uneven area, measure the depth at several points and use the average.
Treating bulk and bags the same. A cubic yard is 27 bags of 1 cu ft. For more than about a cubic yard, bulk delivery is usually cheaper.
To convert the answer to cubic meters, use cubic yards to cubic meters.