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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.

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