Key takeaway: The average Australian backyard pool holds around 48,000 litres, roughly 50 times smaller than an Olympic pool’s 2,500,000 litres. Work out your own pool’s volume with length × width × average depth × 1,000.
“How big is my pool, actually?” is a harder question than it sounds, because the number that matters for chemical dosing isn’t the length and width on the plans, it’s the litres of water actually sitting in it. This guide is the hub for pool sizes, dimensions and the facts we get asked about most, and every dosing calculation elsewhere on this site starts from the numbers below.
Common Australian Backyard Pool Sizes
| Pool type | Typical dimensions | Average depth | Approx. litres |
| Small plunge pool | 3 to 4m × 2 to 2.5m | 1.0 to 1.2m | 9,000 to 10,000 L |
| Small family pool | 6m × 3m | 1.5m | ~27,000 L |
| Medium family pool | 8m × 4m | 1.5m | ~48,000 L |
| Large family pool | 10m × 5m | 1.6m | ~80,000 L |
| Backyard lap pool | 12m × 3m | 1.4m | ~50,000 L |
| 25m residential lap pool | 25m × 3.5m | 1.4m | ~123,000 L (estimated) |
| Olympic pool | 50m × 25m | 2m minimum | 2,500,000 L |
Above-ground pools sit at the smaller end of this range, typically 11,000 to 34,000 litres, limited by a wall height of around 1.2 to 1.8m. A constant-depth plunge pool is the exception to the “sloping” rule below; everything larger than that usually slopes from a shallow to a deep end.
How to Work Out Your Pool’s Volume
The formula is length (metres) × width (metres) × average depth (metres) × 1,000 = litres. The part almost every guide glosses over is “average depth”: it’s the shallow-end depth plus the deep-end depth, divided by two, not the deep end on its own.
Worked example: an 8m × 4m pool with a 1.2m shallow end and a 1.8m deep end has an average depth of (1.2 + 1.8) ÷ 2 = 1.5m. That’s 8 × 4 × 1.5 = 48 cubic metres, and 48 × 1,000 = 48,000 litres. Every chemical dosing instruction on this site, and on every product label you’ll ever read, assumes you’ve got this number right first.
Standard AU backyard pool depth runs 1.0 to 1.8m, sloping to the deep end. If you’re correcting chemistry against one of our guides, our Pool Water Chemistry 101 hub and the dosing guides underneath it all assume you’ve worked out this litre figure first.
Above-Ground vs Inground Pools
Most Australian pool-builder sites only sell inground pools, so this comparison is genuinely under-covered elsewhere. Above-ground pools run smaller (roughly 11,000 to 34,000 litres) because they’re limited by wall height rather than dug depth, which also means faster temperature swings and, usually, a shorter chemical dosing calculation. Inground pools average 40,000 to 60,000 litres or more, with fibreglass, concrete and vinyl-liner builds all capable of the same broad size range; it’s the construction type, not the size, that changes maintenance.
Frequently Asked Questions
How many litres in an average Australian backyard pool?
Roughly 40,000 to 60,000 litres for a typical inground family pool.
How many litres in an 8m x 4m pool?
About 48,000 litres at a 1.5m average depth. See the worked example above for the full calculation.
What is a good size for a family pool in Australia?
Most families land in the 7 to 9m long, 3 to 4m wide range, which comfortably holds a medium to large family pool worth of water.
How deep should a backyard pool be?
Typically 1.0 to 1.8m, sloping from the shallow end to the deep end. A plunge pool is the exception, usually a constant 1.0 to 1.2m.
How long is a lap pool?
Backyard lap pools commonly run 12 to 25m long by 2 to 4m wide, well short of a 50m Olympic pool.
How many litres in an Olympic pool?
2,500,000 litres: 50m by 25m at a minimum depth of 2m, per World Aquatics.
How do you calculate pool volume in litres?
Length times width times average depth, times 1,000. Average depth is the shallow-end and deep-end depths added together and divided by two, not the deep end alone.
What is the difference between above-ground and inground pool sizes?
Above-ground pools hold roughly 11,000 to 34,000 litres, limited by wall height. Inground pools average 40,000 to 60,000 litres or more.
What is the standard depth for a plunge pool?
Around 1.0 to 1.2m, at a constant depth rather than sloping to a deep end.
Is a 6m x 3m pool big enough for a family?
Yes. It holds around 27,000 litres and suits most suburban blocks.
