How Much Soil for a 12×4 ft Raised Bed (8 Inches Deep)?
Calculate the cubic yards of soil needed to fill a 12 ft × 4 ft raised bed to an 8-inch depth.
How to use this tool
- Enter the inside dimensions of your raised bed in feet.
- Enter the depth of soil you need to fill in inches (10–12 in is standard).
- The calculator returns cubic feet, cubic yards, and the number of 40-litre bags to buy.
A 12-foot raised bed is a popular choice for longer rows — this calculator shows the exact soil volume at an 8-inch fill depth.
Frequently asked questions
- How much soil do I need for a raised bed?
- Multiply the inside length × width (ft²) by the fill depth in feet (inches ÷ 12). A 4×8 ft bed filled 12 inches deep needs 32 cubic feet of soil.
- What soil mix is best for raised beds?
- A popular recipe is the Mel's Mix: 1/3 compost, 1/3 peat moss or coir, and 1/3 coarse vermiculite. This provides excellent drainage and nutrient retention.