Pool Calculator for Canada

How to calculate pool volume in Canada

To calculate pool volume, measure length, width and average depth, multiply the three together, then convert to your unit. In metres: Length × Width × Average depth × 1,000 = litres. A 16 × 32 ft pool (4.9 × 9.8 m) at 5 ft average depth holds about 19,200 US gallons — roughly 72,700 litres. Average depth means (shallow end + deep end) ÷ 2. Always measure the water itself, not the wall height: walls overstate the water you actually treat, and every chemical dose follows from this number.

Above-ground pools: round and oval volumes

Most Canadian backyard pools are above-ground round or oval models with 48" or 52" walls — and water sits about 6 inches below the wall top, so use water depth, not wall height. A round pool volume calculator uses π × radius² × depth: a 24 ft round pool at 4 ft of water holds about 13,600 US gallons (≈51,500 litres). Oval pools use π × (length ÷ 2) × (width ÷ 2) × depth: an 18 × 33 ft oval at 4 ft holds about 10,600 gallons (≈40,100 litres). Kidney and freeform pools use the 0.45 industry estimate (±10%) — add two-thirds of any dose, retest, then top up.

Gallons, litres and which gallon your label uses

Canada straddles both systems, so always check which gallon your chemical label uses: 1 US gallon = 3.785 litres, while older imperial measures run larger. Our pool volume calculator shows US gallons and litres side by side — 1 cubic metre equals exactly 1,000 litres — so you can match whichever unit the label uses without manual conversion. When in doubt, dose by litres: Canadian labels increasingly read mg/L, numerically identical to ppm.

Why pool volume matters for chemicals

Every dose is per unit of water: free chlorine at 1–3 mg/L, salt systems at 2700–3400 mg/L, and hydrochloric acid to hold pH at 7.2–7.6. Dose off the wrong volume and you under-dose into algae or over-dose into bleached liners and wasted product. Calculate volume first in our pool chemical calculator, then carry the number into chlorine and salt pool calculator — they pick it up automatically.

Common Canadian pool sizes

Olympic swimming pool volume

An Olympic swimming pool holds 2,500 cubic metres of water: 2,500,000 litres, about 660,000 US gallons. A typical 19,200-gallon backyard pool is roughly one-thirty-fourth of that — a handy sanity check that your own result sits in a believable range.

Closing for winter starts with volume

Canadian pools close for months, and closing chemicals are dosed by volume just like summer ones — winterizing kits, antifreeze-safe algaecide and chlorine shock all scale to your litres. Know your exact volume before you buy the kit, balance the water one last time, then follow our pool closing checklist. Come spring, the same number drives your refill and startup costs.