Swimming Pool Volume & Fill Time
Calculate the volume of a sloped-bottom swimming pool in cubic metres (kilolitres) and estimate the fill time based on your water supply flow rate.
Results
What is it?
A swimming pool volume calculator uses the average depth method to estimate pool capacity in cubic metres (equivalently, kilolitres � 1 m3 = 1 kL). This matters for chemical dosing, water bills from council fill permits, and pump/filter sizing, which are all rated per kilolitre.
How to use
Enter pool length and width, then shallow and deep end depths. The calculator averages the two depths to estimate volume for a uniformly sloping bottom � the standard shape for residential pools. Enter your fill rate (check your water meter during a hose test) to get the fill time in hours.
Example scenario
A 10 x 5 m pool with a 1 m shallow end and 2 m deep end has an average depth of 1.5 m, giving 75 m3 (75 kL). Using a 2 kL/hr hose, filling takes 37.5 hours � about 1.5 days. At typical water rates, 75 kL costs $150�$250 depending on your local tariff.
Pro tip
Pool chemical dosing (chlorine, pH adjusters) is calculated per 1,000 L (1 kL) of water. Knowing your exact volume prevents under- or over-dosing. For irregular-shaped pools (kidney, L-shape), break them into rectangular sections and sum the volumes. Pool volume also determines your pump turnover rate � aim for full circulation every 6�8 hours.