Washing Machine Capacity Calculator

How it works

weekly laundry = people × kg per person · load = weekly laundry ÷ washes a week · capacity ≥ load ÷ 0.8 (drum about 80% full), rounded up to a standard size · US drum ≈ capacity in kg ÷ 2 cu ft

Washing machine capacity is the maximum dry weight of cotton laundry the drum takes on its main programme, as rated under IEC 60456. A typical person produces 3–6 kg of dry laundry a week, so a household's weekly total divided by the number of washes is the load size. Filling the drum to about 80% leaves room for the clothes to tumble and rinse, so the right capacity is that load divided by 0.8, rounded up. Larger drums also let you wash duvets and bedding at home; washing fewer, fuller loads saves water and energy. In the US, washers are sold by drum volume — roughly 2 kg of laundry per cubic foot.

Worked example

A family of 4 with average laundry produces 4 × 4.5 = 18 kg a week. Washing 3 times a week, each load is 6 kg; at 80% fill the drum should hold 7.5 kg, so the recommended size is an 8 kg (17.6 lb) washer — about 4.0 cu ft in US terms.

Sources: IEC 60456 — Clothes washing machines for household use: methods for measuring performance · ENERGY STAR — Clothes washers

Frequently asked questions