How Much Topsoil Do I Need?

- September 25, 2026

Landscaping Guide

Topsoil is sold by volume, so estimating it requires both the surface area of your project and the depth of soil you want to add.

Quick answer: multiply the project area by soil depth to calculate cubic feet, then divide by 27 to convert cubic feet into cubic yards.

Calculate topsoil automatically

Enter your area and soil depth to estimate cubic yards and bag quantities.

Use the Topsoil Calculator Calculate Area

Topsoil Calculation Formula

Area = Length × Width

Depth in Feet = Depth in Inches ÷ 12

Cubic Feet = Area × Depth

Cubic Yards = Cubic Feet ÷ 27

Example: 20 ft × 15 ft Garden Bed

The area is:

20 × 15 = 300 ft²

If you want 4 inches of topsoil:

4 ÷ 12 = 0.333 ft

Volume:

300 × 0.333 = about 100 ft³

Convert to cubic yards:

100 ÷ 27 = about 3.70 yd³

You would need approximately 3.7 cubic yards before any extra allowance.

How Much Area Does One Cubic Yard Cover?

Depth	Approx. Coverage per Cubic Yard
1 inch	324 ft²
2 inches	162 ft²
3 inches	108 ft²
4 inches	81 ft²
6 inches	54 ft²

How Deep Should Topsoil Be?

The right depth depends on what you are doing.

Adding a thin layer to improve an existing lawn is very different from filling a new raised bed or establishing a completely new planting area.

Use project-specific guidance rather than assuming one depth fits every application.

Topsoil for a Lawn

For lawn projects, soil may be used for grading, filling low areas, establishing new turf or lightly topdressing an existing surface.

A small change in depth can dramatically change quantity over a large yard.

Example: 1,000 ft² Lawn

Depth	Cubic Feet	Cubic Yards
1 inch	83.3 ft³	3.09 yd³
2 inches	166.7 ft³	6.17 yd³
3 inches	250 ft³	9.26 yd³
4 inches	333.3 ft³	12.35 yd³

Topsoil for Raised Beds

A raised bed is calculated like a rectangular volume:

Volume = Length × Width × Soil Depth

A raised bed measuring 8 ft × 4 ft with 1.5 ft of fill volume requires:

8 × 4 × 1.5 = 48 ft³

48 ÷ 27 = 1.78 yd³

Raised beds are often filled with a soil blend rather than pure topsoil alone. The appropriate blend depends on what you are growing.

How Many Bags of Topsoil Do I Need?

Once you know cubic feet, divide by the volume printed on the bag.

Bags Needed = Total Cubic Feet ÷ Bag Volume

If you need 24 ft³ and the bags contain 1.5 ft³:

24 ÷ 1.5 = 16 Bags

Bulk vs Bagged Topsoil

Bagged soil is convenient for small projects. Bulk delivery can be more practical for several cubic yards.

When comparing prices, convert both options into cost per cubic yard.

Does Topsoil Settle?

Loose soil can settle after spreading, watering and natural consolidation.

How much it settles depends on soil texture, moisture, compaction and organic content.

A small additional quantity may be useful for grading and touch-ups, but avoid excessive compaction in planting areas.

How to Measure an Irregular Yard

Break the area into smaller rectangles or simple shapes and add the areas together.

Then apply the soil depth to the combined area.

Topsoil vs Mulch

Topsoil is used to create or improve the soil layer. Mulch is normally placed on top of soil as a surface covering.

Use our Mulch Calculator if you are estimating a finishing mulch layer.

Calculate soil for your project

Estimate cubic yards before ordering a bulk delivery or bags.

Calculate Topsoil

Common Topsoil Calculation Mistakes

Forgetting to Convert Inches to Feet

Four inches is 0.333 ft, not 4 ft.

Confusing Cubic Feet With Cubic Yards

One cubic yard equals 27 cubic feet.

Ignoring Existing Grade

Some areas may require more soil than others.

Buying Soil Before Checking Quality

Topsoil composition can vary significantly between suppliers.

Frequently Asked Questions

How many square feet does a yard of topsoil cover?

One cubic yard covers about 324 ft² at 1 inch, 162 ft² at 2 inches, 108 ft² at 3 inches or 81 ft² at 4 inches.

How many cubic feet are in a cubic yard?

There are 27 cubic feet in one cubic yard.