Washing machine capacity is the weight of dry laundry the drum is designed to wash in a single cycle. A 7kg machine washes about 35 T-shirts; a 10kg machine washes a king size duvet. The right size depends on how many people are in the house and what you wash, not on the size of the kitchen.
A rule of thumb
- 7kg to 8kg: one or two people, two or three washes a week.
- 9kg: a family of three or four with school uniforms and sports kit.
- 10kg: a family of four or more, or anyone who washes bedding and towels at home every week.
- 11kg to 13kg: large households, big families, or a duvet-and-towels habit.
Why bigger is not always better
A large drum run half full uses nearly as much water and electricity as a full one, because the machine heats a drum of water regardless. Auto-weighing machines reduce the waste but do not remove it. The other cost is depth: most 10kg and larger machines are 63cm to 66cm deep rather than 55cm to 60cm, which matters under a worktop or in a narrow utility room.
Spin speed and capacity together
Larger drums pair with 1400rpm or 1600rpm spin speeds, which leave clothes drier for the tumble dryer or the airer. A 1400rpm spin on a 10kg load removes more water than a 1200rpm spin on an 8kg load. If you tumble dry everything, the higher spin pays back in dryer time.
Integrated machines
Integrated washing machines, which sit behind a kitchen door, are limited by the cabinet depth and top out at around 10kg; most are 7kg to 9kg. If you need more than that, the machine will have to be freestanding.
Measuring up
Standard machines are 60cm wide and 85cm tall. Measure the depth of the space to the wall and allow 5cm behind for the hoses and 2cm either side. Check the door swing if the machine sits beside a wall or a return of units.
Browse washing machines by capacity, or read our heat pump dryer guide if you are replacing both.