Calculate pool volume in kilolitres and litres for rectangular, round, oval, kidney and freeform pools.
For a rectangular pool: volume (m³) = length × width × average depth. Average depth = (shallow end + deep end) / 2. Then multiply by 1000 to get litres. An 8 × 4 m pool with 1.0 m shallow and 1.8 m deep has an average depth of 1.4 m and volume of 44.8 m³ = 44,800 L.
At typical NZ water rates of $1.50–$2.50 per m³ (1 kL), a 50 kL pool costs $75–$125 to fill from a metered supply. Some councils charge more for large volumes. Consider using a water tank or tanker delivery for very large pools in water-restricted areas.
A typical residential garden hose delivers 10–15 L/min. At 12 L/min, a 50,000 L pool takes about 70 hours (3 days). A 25 mm fill hose can deliver 40–60 L/min, filling the same pool in 14–21 hours. This calculator estimates fill time at 250 L/min (standard household water main).