How Many Bags of Soil for a Raised Bed?

A quick way to estimate soil bags for any raised bed size and depth, plus bag size comparisons (2 vs 3 cu ft).

Quick answer

1) Compute soil(ft³)=L×W×(depth_in/12). 2) Bags=ceil(soil_ft³/bag_ft³). For 2 vs 3 cu ft bags, 3 cu ft usually means fewer bags but heavier handling.

Worked example

Example: 4×8 bed at 12": soil=32 ft³. 2 ft³ bags: 32/2=16 → 16. 3 ft³ bags: 32/3=10.67 → 11. 1.5 ft³ bags: 32/1.5=21.33 → 22.

“How many bags” depends on your depth, whether you fill to the brim, and whether you use layered fill (Hügelkultur style) or pure soil mix.

Use the calculator Opens prefilled state.

Is 2 cu ft or 3 cu ft better?

2 cu ft bags are easier to carry; 3 cu ft means fewer trips but heavier bags.

Why does my store calculator differ?

Stores may include settling buffers or assume different bed shapes.

What’s a typical raised bed soil depth?

Common depths are 10–12 inches, but goals and crops matter.

Do I need compost too?

Many mixes include compost; if you add it separately, reduce bagged soil accordingly.

Estimates only. If you need accuracy, validate depth, compaction, and spacing with your local guidance.