Topsoil Calculator: The Complete Guide to Estimating Cubic Yards, Tons, and Cost
Good topsoil is the foundation of every successful garden, lawn, and landscape. Whether you're establishing a new lawn from seed, filling raised beds for vegetable gardening, or amending existing garden beds, calculating the right amount saves money and ensures your plants get the depth of quality soil they need to thrive.
The Topsoil Formula
Volume (cu ft) = Length × Width × Depth (in) ÷ 12
Cubic Yards = Volume ÷ 27
Tons = Cubic Yards × Density (1.1 t/yd³ for screened)
40 lb Bags ≈ Cubic Yards × 36
Quick Rule: 1 cu yd covers 324 sq ft at 1" deep
Quick Rule: 1 cu yd covers 81 sq ft at 4" deep
Worked Example — New Lawn (1,000 sq ft, 4" deep)
Area: 1,000 sq ft, Depth: 4 inches
Volume: 1,000 × 4 ÷ 12 = 333.3 cu ft
Cubic yards: 333.3 ÷ 27 =
12.35 cu ydTons: 12.35 × 1.1 =
13.6 tonsCost: 12.35 × $30 =
$371 (bulk delivery)Bag equivalent: ~445 bags of 40 lb =
$1,335-$3,115 (much more expensive!)
Soil Types and Uses
| Type | Weight (t/yd³) | Cost/yd³ | Best For |
|---|
| Screened Topsoil | 1.1 | $20-$40 | Lawns, general landscaping, grading |
| Garden Mix | 0.9 | $35-$55 | Flower beds, vegetable gardens |
| Compost (pure) | 0.6 | $40-$70 | Amendment (mix with soil 25-50%) |
| Raised Bed Mix | 0.8 | $40-$60 | Raised beds, containers |
| Fill Dirt | 1.0 | $10-$25 | Grading, backfill (not for planting) |
Pro Tip — Topsoil Quality Matters
Not all topsoil is equal. Ask suppliers about: screening mesh size (1/2" screen removes most rocks), organic matter content (5-10% is ideal), pH (6.0-7.0 for most plants), and whether it's been tested for contaminants. Dark color indicates good organic content. Cheap unscreened "topsoil" is often just subsoil or fill dirt with clay and rocks. For vegetable gardens, insist on screened topsoil or garden mix with documented organic content.
Critical — Don't Bury Existing Plant Roots
When adding topsoil to an existing lawn, never add more than 1 inch at a time — thicker layers smother grass and suffocate roots. For lawn renovation, add 1" of topsoil, rake level, wait for grass to grow through (2-3 weeks), then add another inch if needed. For new lawns on bare ground, 4-6" of topsoil is ideal. For raised beds, use raised bed mix (not pure topsoil) for better drainage and aeration.