Pond Calculator

Need to estimate how much water you'll need to fill a pond and what size of pond liner to get for your pond? Try our pond calculator now to answer those questions.

Water volume4,578 US gallons17,330 litres · 612 cu ft

Surface area204 sq ftfreeform, taken as 85% of the bounding rectangle

Average depth3 ft2 ft to 4 ft

Weight of the water19.1 US tons17,330 kg

Chlorine to raise by 1 ppm0.61 ozof pure chlorine, by weight

Volume in 10,000-gallon units0.458most pool chemicals are dosed per 10,000 gallons

Time to fill at 10 gal/min7:38a typical garden hose

The method

volume = area × average depth

Average depth, not maximum

A pool that runs from 3 to 8 feet averages 5½ feet, so it holds about a third less than the deep end suggests. Getting this wrong throws off every chemical dose, because they are all quoted per volume.

Freeform pools never fill their bounding rectangle. Taking 85% of length × width is the usual approximation for a kidney shape, and it is worth checking against the actual fill volume once you know it.

Turnover is the figure the plant is sized on: most codes want the entire volume passed through the filter in six to eight hours, which for a typical residential pool means 40–60 gallons a minute.