Topsoil for a 12×12 ft garden bed
A 12 × 12 ft garden bed at 8 in deep needs 3.56 cubic yards of topsoil — about 96 × 40 lb bags, roughly 4.32 tons and $124.44 of material. Fine-tune below.
Full breakdown
| Item | Value |
|---|---|
| Volume before waste | 96.0 ft³ |
| Volume with 10% waste | 105.6 ft³ |
| Cubic yards | 3.91 |
| Cubic metres | 2.99 |
| Cubic feet | 105.6 |
| Weight | 4.75 tons (9,504 lb) |
| Full dump-truck loads | 1 × 10 yd³ truck |
| 40 lb bags | 106 bags · $344.50 |
| Sq ft covered at 1 in deep | 1,267 |
| Sq ft covered at 3 in deep | 422 |
- Formula: length × width × depth, with depth converted from inches to feet (÷ 12), then × (1 + waste%).
- Topsoil: Topsoil is sold screened or unscreened by the cubic yard; for lawns you want screened loam, and for filling low spots unscreened is fine and cheaper.
- Topsoil settles 15–25% after watering and compaction, so a 6-inch loose layer becomes roughly 4½ to 5 inches once it has rained twice. Order on the settled depth you need.
- Prices are national averages for planning, not quotes. Confirm with a local supplier — delivery, short-load fees and tax are extra.
For a 12 × 12 ft garden bed at 8 in, you need 3.56 cubic yards of topsoil (96.0 ft³, about 4.32 tons) before any extra you add for waste.
The calculator above is pre-filled with these dimensions — change any field to see the numbers update. Topsoil is sold screened or unscreened by the cubic yard; for lawns you want screened loam, and for filling low spots unscreened is fine and cheaper.
Frequently asked questions
How many cubic yards of topsoil for a 12×12 ft garden bed?
About 3.56 cubic yards at 8 in deep, which is 96.0 cubic feet or 4.32 tons. Add 10% waste if the ground is uneven.
How many bags is that?
96 × 40 lb bags, or 96 × 40 lb bags. Bagged is only worth it at this size if you cannot take a truck delivery.
What depth should a garden bed be?
8 in is the standard for topsoil in this application. Topsoil settles 15–25% after watering and compaction, so a 6-inch loose layer becomes roughly 4½ to 5 inches once it has rained twice. Order on the settled depth you need.