Soil Calculator
Topsoil in bags, cubic yards or tons — with one-click raised-bed presets.
Quick answer
Multiply length × width × depth (all in feet) to get cubic feet of soil, then divide by 27 for cubic yards. A classic 4×8 ft raised bed filled 10 inches deep needs about 27 cubic feet — one full cubic yard, or roughly 27 one-cubic-foot bags. Soil is heavy: a cubic yard of topsoil weighs roughly 1 to 1.3 tons.
Reference chart
| Raised bed | Depth | Soil needed |
|---|---|---|
| 4 × 4 ft | 10 in | 13.3 cu ft (≈ 0.5 cu yd) |
| 4 × 8 ft | 10 in | 26.7 cu ft (≈ 1 cu yd) |
| 3 × 6 ft | 12 in | 18 cu ft (≈ 0.67 cu yd) |
| 2 × 8 ft | 10 in | 13.3 cu ft (≈ 0.5 cu yd) |
Good to know
Filling a raised bed: not just topsoil
Most gardeners fill raised beds with a blend rather than pure topsoil — a common mix is roughly 60% topsoil, 30% compost and 10% aeration material (like perlite or coarse sand). Calculate the total volume with this tool, then split it by your chosen ratio.
Soil is heavier than people expect
A cubic yard of topsoil weighs roughly 2,000–2,600 lb (about 1–1.3 tons), more when wet. That's beyond most car suspensions and many small trailers — for anything over half a yard, delivery is usually the sensible choice.
Allow for settling
Fresh soil settles by roughly 10–20% in the first weeks as it compacts and waters in. Slightly overfill new beds, or plan a top-up bag or two, so your bed doesn't end up short.