Compost Bin Capacity
Calculator

It calculates the bin's interior volume (length times width times height for rectangular bins, or the cylinder formula for round ones) to tell you how much raw material it can hold, which is useful for sizing a bin to your household's typical food and yard waste output.

As organic material decomposes, it loses volume through moisture evaporation, gas release, and the physical breakdown of plant structure, typically shrinking to about 30-50% of its original volume, so a bin that looks full of fresh scraps will have much more room once that material breaks down.

A general estimate is that a family of four generates roughly 1-2 cubic feet of compostable kitchen scraps per week, so matching bin capacity to how often you plan to empty or turn the pile determines the minimum size that won't overflow between cycles.

Yes, a pile needs a minimum volume of roughly one cubic yard (3x3x3 feet) to generate and retain enough heat for efficient hot composting; smaller bins can still compost successfully, but more slowly through cooler, more passive decomposition.

No, leave some headroom for turning and mixing the material, since compost needs regular aeration to decompose efficiently, and a bin packed to the brim is difficult to turn and tends to compact, which slows decomposition rather than speeding it up.