Calculate, compare, understand, decide
Water Consumption Calculator
Estimate daily and monthly household water use by activity, compare it with your meter and test illustrative conservation scenarios.
Smart result
Your estimate will appear here
Change any editable assumption, calculate, then review the steps, assumptions and limitations before deciding.
How this estimate works
Per-person uses (bathing, flushing, handwashing) are multiplied by household size and added to household uses. Weekly laundry is converted to a daily figure. Daily litres × 30 gives the monthly total.
Formula
- Daily = people × (bathing + flushes × L/flush + handwash) + kitchen + loads × L/load ÷ 7 + cleaning + garden
- Monthly = daily × 30; kL = litres ÷ 1,000
- Conservation = daily − Σ(category × saving %)
Limitations
- Habit values are examples, not measurements.
- Conservation savings are illustrative.
Data used
No official dataset is used. Every rate, price and premium is entered by you or is a labelled, editable assumption.
Related calculators
Frequently asked questions
What is a kilolitre?+
1 kilolitre (kL) is 1,000 litres, the unit many water bills use.
My meter shows a different number. Which is right?+
The meter. Adjust the habit values until the estimate is close, or check for leaks if the meter is much higher.
How accurate is this water use estimate?+
It will provide an indicative estimate based on your inputs and the stated assumptions. Actual results can vary by location, equipment, tariff, and usage.
Can I use the result to make a purchase?+
Use it as a starting point, then confirm current prices, specifications, eligibility, and site requirements with a qualified provider.