Topsoil Calculator
To calculate topsoil, multiply the area length by width, then by depth in feet, and divide by 27 for cubic yards. A 20×10 ft bed at 3 inches deep needs about 1.85 cubic yards, or roughly 67 bags of 40-lb topsoil.
- New beds
- 4–6 in deep
- Top-dressing
- ¼–½ in
- 1 yd³ covers
- ~108 ft² at 3 in
Your measurements
2–3 in to top-dress, 4–6 in for new beds.
Enter your measurements
Fill in the fields to see your estimate.
The formula
Topsoil (yd³) = (Length ft × Width ft × Depth ft) ÷ 27How to calculate it manually
- 1
Measure the area
Record length and width in feet.
- 2
Choose a depth
2–3 in to improve a bed, 4–6 in to build a new one, ¼–½ in to top-dress a lawn.
- 3
Find the volume
Multiply area × depth, then divide by 27 for cubic yards.
- 4
Convert to bags
One cubic yard is about 36 bags of 0.75 ft³ (40 lb) topsoil.
Example calculation
A 20 ft × 10 ft bed at 3 in: 200 ft² × 0.25 ft = 50 ft³ ÷ 27 ≈ 1.85 yd³.
Topsoil coverage by depth
Area one cubic yard of topsoil covers.
| Depth | Coverage per yd³ |
|---|---|
| 1 in | 324 ft² |
| 2 in | 162 ft² |
| 3 in | 108 ft² |
| 6 in | 54 ft² |
Common topsoil estimating mistakes
Buying bags for big areas
Above ~2 cubic yards, bulk delivered topsoil is far cheaper than bagged.
Ignoring settling
Loose topsoil settles 10–20%. Add a little extra, especially in new beds.
Wrong depth for the job
Top-dressing a lawn needs only ¼–½ inch; piling it deeper smothers grass.
Frequently asked questions
Related guides
Related calculators
Ready to start your landscaping project?
Run the numbers above, then explore related tools and guides to plan every step.