Topsoil Calculator
Enter the area and the depth of soil you need to get cubic yards to order, an estimated weight in tons and a count of bags. Choose topsoil, sand or fill dirt, or type your supplier’s density.
Quick answer: A raised bed 8 ft × 4 ft filled 12 in deep is 1.19 cubic yards of topsoil, or 1.30 yd³ with a 10% settling allowance, about 1.43 tons at 1.1 tons per cubic yard.
Topsoil volume is area × depth. Multiply length by width in feet, multiply by the depth in feet (inches ÷ 12), then divide by 27 for cubic yards. Multiply cubic yards by the density in tons per yard for weight.
Example: a raised bed 8 ft × 4 ft filled 12 in deep is 32 ft³, or 1.19 yd³. With a 10% settling allowance that is 35.2 ft³, or 1.30 yd³, about 1.43 tons at 1.1 tons per cubic yard.
Method
How this calculator works
The volume is exact geometry. The weight is an estimate from an editable density, because soil weight swings with moisture and organic content.
Volume at the depth you choose
There is no standard depth: a raised bed is deeper than a lawn patch, so the depth is yours to enter. Inches are divided by 12 to get feet.
Volume (ft³) = L (ft) × W (ft) × Depth (in) ÷ 12Cubic yards = Volume (ft³) ÷ 27Settling allowance
Soil settles after it is placed and ground is rarely level. The calculator starts at 10% and lets you pick 0 to 25%. It is a typical allowance, not a rule, so adjust it for your job. The order is also shown rounded up to the next quarter yard.
Order volume = Net yd³ × (1 + Allowance ÷ 100)Weight in tons
Short tons (2,000 lb) per loose cubic yard. Starting values: dry topsoil 1.1, moist topsoil 1.28, dry sand 1.35, wet sand 1.6, fill dirt 1.1. They come from calculator-site and supplier-style tables, not a standard. Type your supplier’s density to override.
Tons = Order yd³ × Density (tons per yd³)Bags
Bag size is printed on the bag. Extension tables list 0.75, 1, 1.25 and 2 cubic feet for soil and compost bags. The calculator starts at 1 ft³ and rounds up. Clear the field to hide the bag count.
Bags = round up (Volume with allowance (ft³) ÷ Bag size (ft³))Worked example: a raised bed 8 ft × 4 ft, 12 in deep, 10% allowance
Arithmetic checked| Step | Math | Result |
|---|---|---|
| Area of the bed | 8 × 4 | 32 ft² |
| Volume at 12 in | 32 × (12 ÷ 12) | 32 ft³ |
| Convert to cubic yards | 32 ÷ 27 | 1.1852 yd³ |
| Add a 10% settling allowance | 32 × 1.10 = 35.2 ft³; 35.2 ÷ 27 | 1.3037 yd³ |
| Round up to the next 0.25 yd³ | 1.3037 → 1.5 | 1.5 yd³ |
| Weight at 1.1 tons per yd³ | 1.3037 × 1.1 | 1.434 tons |
| Bags of 1 ft³ | 35.2 ÷ 1, round up | 36 bags |
| Bags of 0.75 ft³ | 35.2 ÷ 0.75 = 46.93, round up | 47 bags |
| You would order | about 1.3 yd³ (1.5 yd³ delivered), or 36 bags (1 ft³) | |
Disclaimer
Results are planning estimates based on the dimensions and assumptions you enter. They are not engineering, structural or building-code advice. Product yields, densities and coverage vary by manufacturer, batch and site conditions. Check product labels, your supplier and your local building department before you order materials or start work. Read the full calculation disclaimer.
Accuracy
What affects your estimate
The yardage is dependable. The tonnage and the bag count depend on things the calculator cannot see.
Moisture
Wet soil is heavier. The presets move from 1.1 tons per yard for dry, loose topsoil to 1.28 when moist, and from 1.35 to 1.6 for dry and wet sand. If the pile has been rained on, pick the wetter preset or ask your supplier.
Organic content
Mixes made with compost are lighter than mineral soil. Manufactured topsoil can sit well below the preset, so a supplier’s figure beats ours.
Settling
Loose soil compacts under its own weight and with watering. The 10% default covers some of it. A deep fill has more soil to settle, so consider a higher allowance there.
Bulk or bags
Bags are convenient for small beds. Past a couple of cubic yards, compare a delivery with bags at your own suppliers, including delivery charges.
This calculator does not judge soil quality, drainage or grading. Weight is an estimate, and suppliers sell by the yard or by the ton, so ask which, and for their density.
Common mistakes
Using the dry weight for wet soil
Rained-on soil weighs more than the dry preset suggests. If you buy by the ton, a wetter pile means each ton covers less volume than you planned.
Forgetting the depth for a raised bed
A bed 4 ft × 8 ft filled 12 in deep needs about 1.2 yd³. At 3 in it needs 0.3 yd³. Enter the real fill depth, not the board height.
Trusting the bag size from memory
Soil bags range from 0.75 to 2 cubic feet. Read the label, type the size, and let the count round up.
Questions people ask
How do you work out how much topsoil you need?
Multiply length by width in feet and by the depth in feet (inches ÷ 12), then divide by 27 for cubic yards. Add a settling allowance of about 10%. The guide on how much topsoil you need adds typical depths for lawns and raised beds.
How much soil do I need for a raised bed?
For a bed 8 ft × 4 ft filled 12 in deep, 32 ft³ is 1.19 yd³, or 1.30 yd³ with a 10% allowance. Enter the depth of soil, not the height of the frame.
How much area does 3 cubic yards of topsoil cover?
3 yd³ is 81 ft³. That covers 324 ft² at 3 in deep, or 162 ft² at 6 in deep.
How many tons of sand do I need for 500 square feet at 2 inches?
500 × (2 ÷ 12) = 83.33 ft³, or 3.09 yd³. At 1.35 tons per yd³ for dry sand that is about 4.17 tons. The guide on cubic yards in a ton lists typical weights for sand, soil and gravel.
How many cubic meters of topsoil are in a tonne?
At the dry-topsoil preset of 1.1 short tons per yd³, one metric tonne is about 0.77 m³. Moist soil is heavier, so the same tonne is less volume.
Related calculators and guides
Sources
Where the numbers come from
- Texas A&M AgriLife Extension (Travis County) volume formula and bag sizes for soil and compost, accessed October 16, 2026.
- Inch Calculator (secondary source) cubic yards to tons (soil and sand density ranges; no primary source cited), accessed October 16, 2026.
- Crushed Stone Calculator (secondary source) weight per yard (fill dirt density), accessed October 16, 2026.
- NIST Handbook 44, Appendix C (cubic yard, ton and tonne definitions), accessed October 16, 2026.