How many bathtubs is that?
A full bath is about 150 litres, which makes it the natural household unit for anything bigger than a bucket.
20 × a bath
3,000 L ÷ 150 L = 20 baths.
Reference figures are measurements and are rounded; the unit conversion behind them is exact.
| Reference | Size | Yours ÷ theirs | Note |
|---|---|---|---|
| toilet flush | 6 L | 500× | |
| bucket | 10 L | 300× | |
| washing machine cycle | 50 L | 60× | |
| shower, 8 minutes | 80 L | 37.5× | |
| bath | 150 L | 20× | A comfortable fill, not to the brim |
Worth knowing
- A bath uses about 150 litres and an eight-minute shower about 80 — so the old advice holds, but by less than people assume.
- A power shower at 15 litres a minute passes a bath’s worth in ten minutes.
Frequently asked
How many litres in a bath?
A standard 1 700 mm tub holds around 230 litres to the overflow, but a normal fill is 130–160 litres.
Is a shower cheaper than a bath?
Usually — an eight-minute electric shower uses about half a bath’s water. A power shower over fifteen minutes uses more.