Soil calculator
How much topsoil or garden soil to fill raised beds, planters or a new lawn: cubic yards for a delivery, or how many bags to pick up.
Your beds take
1.30 cubic yards
- Cubic feet
- 35.2 cu ft
- Bags
- 24 × 1.5 cu ft bag
- Cost in bags
- Cost in bulk
- Compost
- 0.00 cu yd
- Soil
- 1.30 cu yd
- Weight as topsoil
- 1.06 tons
Includes the extra you set. Weight is for loose topsoil at a typical 1,620 lb per cubic yard; wet soil weighs more and bagged mixes much less.
How to calculate soil for a raised bed
Multiply the bed's inside length and width by the soil depth in feet, then add a little extra because loose soil settles once it's watered.
- Cubic feet = length × width × depth in inches ÷ 12 (a round bed: 3.1416 × radius² × depth ÷ 12)
- To buy = cubic feet × (1 + extra ÷ 100), times how many beds that size
- Cubic yards = cubic feet ÷ 27, for a bulk delivery
- Bags = cubic feet ÷ the bag size, rounded up
Worked example
A 4 × 8 ft raised bed, 12 in. deep: 8 × 4 × 12 ÷ 12 = 32 cu ft. With 10% extra that's 35.2 cu ft, or 1.30 cubic yards, or 24 bags of 1.5 cu ft.
Soil for common raised beds
Cubic feet of soil, before any extra for settling.
| Bed | 6 in. deep | 12 in. deep | 18 in. deep |
|---|---|---|---|
| 4 × 4 ft | 8.0 | 16.0 | 24.0 |
| 3 × 6 ft | 9.0 | 18.0 | 27.0 |
| 2 × 8 ft | 8.0 | 16.0 | 24.0 |
| 4 × 8 ft | 16.0 | 32.0 | 48.0 |
| 4 × 12 ft | 24.0 | 48.0 | 72.0 |
Bags in a cubic yard, and how far a yard goes
| Bag | Bags per cubic yard |
|---|---|
| 8 qt bag (0.27 cu ft) | 101.0 |
| 16 qt bag (0.53 cu ft) | 50.5 |
| 0.75 cu ft bag | 36.0 |
| 1 cu ft bag | 27.0 |
| 1.5 cu ft bag | 18.0 |
| 2 cu ft bag | 13.5 |
| Spread depth | Square feet per cubic yard |
|---|---|
| 1 in. | 324 |
| 2 in. | 162 |
| 3 in. | 108 |
| 4 in. | 81 |
| 6 in. | 54 |
Soil questions
How much soil do I need for a raised bed?
Length × width × depth. A 4 × 8 ft bed filled 12 in. deep holds 32 cubic feet; with 10% extra for settling, that's 24 bags of 1.5 cu ft or 1.30 cubic yards. Enter each bed size above, with how many you have, and the calculator adds them up.
How much does a yard of topsoil weigh?
About 1,620 pounds (0.81 tons) loose, as it's delivered, and about 2,430 pounds undisturbed in the ground, according to the Federal Highway Administration's earthwork weights. Wet topsoil weighs more. Bagged garden soil and potting mix are much lighter, because they're mostly compost, bark and peat.
How many bags of soil are in a cubic yard?
A cubic yard is 27 cubic feet, so it takes 18 bags of 1.5 cu ft or 13.5 bags of 2 cu ft. The table above covers other sizes, including quart bags of potting soil. Past a cubic yard or so, a bulk delivery is often cheaper; enter both prices to compare.
What's the difference between topsoil, garden soil and potting soil?
Topsoil is screened native soil from the top layer of the ground, used for lawns, grading and filling beds. Garden soil is usually topsoil blended with compost or other organic matter, for in-ground beds and raised beds. Potting soil, or potting mix, is a lighter mix with little or no actual soil, made for containers so they drain. Check the bag or ask the supplier what's in a blend.
Should I mix compost into raised bed soil?
Many gardeners fill raised beds with a blend of soil and compost, and suppliers sell premixed raised bed blends. Mixes vary, so follow your supplier or local extension office. Enter the compost share above and the calculator splits the order into cubic yards of compost and of soil. For mulching the top of the bed, use the mulch calculator.
Is this different from the dirt calculator?
This page is for growing: beds, planters and lawns, by the bag or the yard. The dirt calculator is for fill dirt: raising grade, filling holes and backfill, with extra for compacting. For any other volume, the cubic feet calculator converts boxes and containers to gallons and quarts.