How Many Litres Is My Pool?
Short answer: multiply length × width × average depth in metres and then by 1,000. An 8 × 4 m pool that is 1 m deep at one end and 1.8 m at the other holds 44,800 litres. The table below lists common pool sizes.
The formula
Rectangle: litres = length × width × average depth × 1,000
Round: litres = 3.1416 × diameter² ÷ 4 × average depth × 1,000
Oval: litres = 3.1416 × length × width ÷ 4 × average depth × 1,000
Measure the water, not the shell: use the water line, which is usually 10 to 15 cm below the coping.
Pool volume table (rectangular pools)
| Size | 1.2 m average | 1.4 m average | 1.6 m average |
|---|---|---|---|
| 4 × 2.5 m (plunge) | 12,000 L | 14,000 L | 16,000 L |
| 6 × 3 m | 21,600 L | 25,200 L | 28,800 L |
| 7 × 3.5 m | 29,400 L | 34,300 L | 39,200 L |
| 8 × 4 m | 38,400 L | 44,800 L | 51,200 L |
| 10 × 5 m | 60,000 L | 70,000 L | 80,000 L |
| 12 × 5 m | 72,000 L | 84,000 L | 96,000 L |
Round above-ground pools
| Diameter | 1.0 m deep | 1.2 m deep |
|---|---|---|
| 3.6 m | 10,179 L | 12,215 L |
| 4.5 m | 15,904 L | 19,085 L |
| 5.5 m | 23,758 L | 28,510 L |
Why the volume matters
- Chemicals. Chlorine, acid and stabiliser doses on the label are given per 10,000 litres.
- Salt. Salt chlorinators need a set salt level, often 4,000 to 6,000 ppm. Each 1,000 ppm in 10,000 litres takes 10 kg of salt, so 44,800 litres at 5,000 ppm needs 224 kg.
- Pump size. Most pools should turn over the whole volume at least once a day. Running costs are in the electricity cost calculator.
- Filling. Water carters deliver by the litre, so knowing the volume avoids paying for too much.
Try the pool volume calculator (litres)
Enter your own numbers below, or open the full pool volume calculator (litres) with the formula and more examples.
This guide is general information with example numbers, not financial, tax or building advice. Your costs and results will differ. Terms
Frequently asked questions
How many litres are in an 8 x 4 m pool?
About 44,800 litres with an average depth of 1.4 m (1 m shallow end, 1.8 m deep end).
How do I work out the volume of a round pool?
Multiply 3.1416 by the diameter squared, divide by 4, then multiply by the depth and by 1,000. A 4.5 m pool 1.2 m deep holds about 19,085 litres.
How much salt does a 50,000 litre pool need?
About 250 kg to bring fresh water to 5,000 ppm.