A Pool Volume Calculator

Pool volume is the number every other pool calculation depends on, because chemicals, heating and pump run times are all dosed per litre rather than per pool.

Pool lengthMetres, measured at the waterline.Pool widthMetres, measured at the waterline.Shallow end depthMetres of water, not the height of the wall.Deep end depthMetres of water at the deep end. Enter the same value as the shallow end for a flat pool.

Volume in cubic metres

Volume in litres: 48,000
Volume in US gallons: 12,680.2585
Average depth: 1.5

Values update as you type. This calculator covers the single scenario its formula assumes — see Common Mistakes for what it leaves out.

The formula this calculator uses

volume = length x width x average depth

V: Volume of water, in cubic metres
L: Length of the pool
W: Width of the pool
d: Average water depth

How to check the result by hand

1
Measure the length and width of the water
Measure at the waterline rather than the coping, and measure the water surface rather than the pool shell. Steps and ledges are better handled as separate shapes.
2
Measure both the shallow and deep water depths
Take the depth to the water surface, not to the top of the wall. A pool filled below the coping holds less than its structural depth implies.
3
Average the two depths
Add them and divide by two. Depths of 1.2 and 1.8 give an average of 1.5, which is the depth of the flat pool holding the same water.
4
Multiply length by width by average depth
Eight times four times 1.5 is forty eight cubic metres. There is no correction factor for a rectangular pool with an evenly sloping floor.
5
Convert to litres and check against the label on your chemicals
Multiply cubic metres by a thousand for litres, or by 264.17 for US gallons. Chemical doses are quoted per thousand or per ten thousand litres, so the conversion has to be right.

For worked examples, common mistakes and the limits of this formula, read the full How To Calculate A Pool Volume page.