Soil Calculator

Soil comes in bulk and in bags. Bulk soil is sold by the cubic yard, and a cubic yard is 27 cubic feet. A common bag holds 1.5 cu ft, so a cubic yard takes 18 of them. Loose soil settles once it is spread and watered, which the sections below explain.

How to use this calculator

1. Choose the shape of the area. Rectangle covers most beds and lawn patches, circle suits a round planting bed, and triangle fits a wedge beside a path.
2. Enter length and width in feet, and the depth in inches. For a bed in a dip or on a slope, measure the depth in several spots and use the average.
3. Set the depth to the soil you plan to spread, not to the hole you dig. Fill a little above the finish line, because soil will settle.
4. Use the cubic yards for a bulk delivery and the bag count for a store trip. Compare both, since a small area is often easier to fill from bags.
5. Add the price per cubic yard from your supplier to see an estimated material cost.

Worked examples

Bags of 1.5 cu ft soil for common bed sizes

Number of 1.5 cu ft bags, exact volume without extra for waste.

Bags or bulk?

Bags suit a small bed, a few planters or a patch you can reach by hand. A cubic yard takes 18 bags of 1.5 cu ft, and each one has to be carried and emptied by hand, so the count shows how much work the job is before you start.

For a whole yard, a lawn area or a bed you dig out and refill, bulk soil is usually the easier choice. Ask the supplier about the smallest load, any delivery charge and where they can tip the pile.

Measuring depth before you order

Measure depth as the gap between the surface you have now and the finish you want. Stakes at the corners and a string line make it easier to find a level top across the whole area.

• Check the surface with a straight board and a level before you measure.
• Measure in several spots and enter the average, not the deepest hole.
• Dig a test hole where the ground looks lowest, because a hidden dip can change the order.

Why loose soil settles

Loose soil sinks as it is watered, walked on and rained on. The air between the particles closes up, and the surface drops over the following weeks. A bed filled exactly to the calculated depth will often end up below the finish line.

The calculator does not add an allowance for settling. If you want one, add a margin to the cubic yards yourself, fill a little above the finish line, and rake the surface level once it has settled.

Leveling low spots and lawn areas

Enter the depth of fill needed at the low point, and the area that needs it. Work in thin layers instead of a thick pour all at once, and let each layer settle before you add the next, because a thick pour over turf is hard to settle evenly.

For large grade changes, drainage problems or a slope that carries water, check local guidance or talk to a landscape professional. This calculator estimates volume only and does not judge how the ground will drain.

How much extra soil should I order for settling?

A common starting point is to add 15 percent to the cubic yards for fill that will be compacted. Adjust it for your soil. Compacted clay typically shrinks 10 to 18 percent, sand 11 to 35 percent, and rocky or gravelly soil 5 to 22 percent.

Common questions