Soil Bag Calculator (Cubic Feet → Bags)

Convert a soil volume in cubic feet into the number of common bag sizes (1.5, 2, 3 cu ft) with a worked example.

Quick answer

Bags = ceil(soil_ft³ / bag_ft³). Example: 32 ft³ with 2 ft³ bags → ceil(32/2)=16 bags.

Worked example

If your bed needs 16 ft³ and you buy 3 ft³ bags: 16/3=5.33 → 6 bags (ceil).

Bagged soil can settle after watering. If you’re topping off or mixing compost, you may need fewer bags than the raw volume suggests.

Use the calculator Opens prefilled state.

Why do you use ceiling (ceil)?

Because you can’t buy a fraction of a bag; you need enough volume.

Should I buy an extra bag?

Often yes for leveling and topping off, but it depends on compaction and your mix.

Do different brands have different true volumes?

They can. The calculator uses the labeled volume as the planning unit.

Is bulk soil cheaper than bags?

Usually, yes at larger volumes. Bags are convenient for small beds; bulk delivery can be cheaper per cubic foot for bigger projects.

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