Pool Calculator for Australia

How to calculate pool volume in litres

To calculate pool volume in litres, measure length, width and average depth in metres, multiply the three together, then multiply by 1,000. That is the whole method behind every pool volume calculator in Australia:

Length × Width × Average depth × 1,000 = litres

A medium 8 × 4 metre pool with 1.5 m average depth holds 8 × 4 × 1.5 × 1,000 = 48,000 litres. Average depth means (shallow end + deep end) ÷ 2 — a pool running 1 m to 2 m averages 1.5 m. Always measure the waterline, not the top of the wall: wall height overstates the water you actually treat, and every chemical dose follows from this number.

Round, oval and kidney pool volumes

A round pool volume calculator uses π × radius² × depth × 1,000 — a 6 m diameter pool at 1.5 m holds about 42,400 litres. Oval pools use π × (length ÷ 2) × (width ÷ 2) × depth × 1,000. Kidney and freeform pools can't be measured exactly, so the industry uses the 0.45 method: 0.45 × (wide lobe + narrow waist) × length × depth × 1,000, accurate to about ±10%. Because it is an estimate, add two-thirds of any dose, retest, then top up — never dose a kidney pool to a single exact number.

Why pool volume matters for chemicals

Every dose on an Australian chemical label is per litre of water: free chlorine at 1–3 mg/L, salt systems at 3000–4000 mg/L, and hydrochloric acid (sold as muriatic acid overseas) to pull pH into 7.2–7.6. Dose off the wrong volume and you under-dose into algae or over-dose into bleached surfaces and wasted product. Calculate litres first in our pool chemical calculator, then carry the same number into chlorine and salt pool calculator — they pick it up automatically.

Common Australian pool sizes in litres

Australia has over 1.35 million residential pools (Roy Morgan, 2024), and most fall into a handful of footprints. Standard fibreglass shells run 7–8 m long:

Litres, kilolitres and cubic metres

How many litres in a cubic metre? Exactly 1,000 — so a 48 cubic metre pool holds about 48,000 litres, often written as 48 kL on water bills and tank specs. If your chemicals carry US labels, convert the other way: 1 US gallon = 3.785 litres, so divide litres by 3.785 for gallons. Our calculator shows both side by side, so you can match whichever unit the label uses without manual conversion.

Olympic swimming pool volume in litres

An Olympic swimming pool holds 2,500 cubic metres of water: 2,500,000 litres, about 660,000 US gallons. A typical 50,000-litre backyard pool is roughly one-fiftieth of that — a handy sanity check that your own result sits in a believable range.

Cost to fill a pool in Australia

Filling from empty costs whatever your retailer charges per kilolitre — find the $/kL figure on your water bill and multiply by your pool's kL. A 50 kL pool at $3/kL is about $150, plus roughly 15% a year in evaporation top-ups. A cover cuts both evaporation and heating loss, which is why our pool cost calculator factors it into every estimate.