Soil Calculator
Buying the right amount of soil saves money and keeps your garden project on schedule. Enter your bed dimensions and desired depth to find out exactly how many cubic yards, bags, or pounds of topsoil you need. This calculator works for garden beds, raised planters, lawn topdressing, and fill projects.
How Soil Volume Is Calculated
The formula: Volume = Length x Width x Depth. The calculator converts inches of depth to feet, then divides total cubic feet by 27 to get cubic yards (the standard bulk delivery unit).
Soil Weight and Bag Estimates
Topsoil weighs roughly 2,200 lbs per cubic yard, though this varies with moisture content and composition. Dry, sandy soil can weigh less (around 1,800 lbs/yd3), while wet clay soil can weigh over 2,600 lbs/yd3.
Bagged soil from garden centers typically comes in:
- 1 cubic foot bags -- common at big-box stores
- 2 cubic foot bags -- the larger "premium" bags
For anything over 3-4 cubic yards, bulk delivery is usually cheaper than buying bags.
Recommended Soil Depths
| Project | Recommended Depth |
|---|---|
| New garden beds | 6-12 inches |
| Raised beds | 12-18 inches |
| Lawn topdressing | 1-2 inches |
| Tree and shrub planting | 12-24 inches |
| Filling low spots | Varies |
Tips for Ordering
Order about 5-10% extra to account for settling and compaction. Soil compresses after watering, so that fresh 12-inch bed might settle to 10 inches within a few weeks.