Shape and Space - Capacity

Capacity is the amount that a container will hold. We usually think of capacity in terms of how much liquid something can contain. Liquids have volume, they take up space and the capacity is a way of describing the amount of space that they take up. Capacity and Volume are similar concepts.

The metric unit of measurement for capacity is the litre (l)
or the millilitre (ml).       1 litre = 1000 millilitres.

Unfortunately, in this country we still use the old imperial units, pints and gallons for measuring capacity for some things. We buy milk and beer by the pint and although we buy petrol by the litre, we talk about fuel consumption in terms of miles per gallon. So your child needs to understand both systems and be able to compare the two. They need to know that:

There are 8 pints in a gallon.

A pint is approximately half a litre.

A gallon is approximately 4.5 litres.

For most things we use the metric system, and it is important for your child to visualise these units and relate them to everyday items. For example:

A teaspoon is approx 5 ml, a dessert spoon is 10 ml and a tablespoon is 15 mlData

DataA bottle of mineral water could be 330 ml or 500 ml

A carton of juice is 1 litre Data


A good idea is to use a kitchen measuring jug to check the capacity of different items - cups, glasses, bottles etc.

They normally have both metric and imperial measurements, so are really useful for comparing the two types of unit.

Capacity and volume are linked together

A hollow cube with a volume of 1 cm³ will hold 1 ml of liquid

A hollow cube with a volume of 1000 cm³ will hold 1 litre of liquid

A hollow cube with a volume of 1 m³ will hold 1000 litres of liquid

Practice working with Capacity with these worksheets from Primary Resources

Investigating Capacity      Filling 1 litre      Capacity ml/l

Capacity Word Problems    Capacity Word Problems 2

Capacity Problems 3      Converting Capacities    

CAT4 / 12 Pus papers