WaterCalcLabWater Consumption Calculator
Scale a measured or selected per-person use over a period.
Your result
Bars compare only results in the same unit group. They are normalized, not a time-series forecast.
Planning result based on your inputs.
How this tool works
Scale a measured or selected per-person use over a period.
V = people × litres/person/day × daysExample calculation
The prefilled form is a worked example. Its base-unit inputs and expected outputs are shown below; use the reset button to restore it.
| Input | Example |
|---|---|
| Number of users | 4 |
| Use per person per day | 100 |
| Days | 21 |
Frequently asked questions
How should I choose the inputs?
Use measurements and local records for the stated period. All preset values are illustrative examples, not recommendations.
What does this result leave out?
Example inputs are not a global average. Use meter readings and add non-person-related demand separately.
Continue your plan
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Method version 1.0 · Last reviewed: 2026-10-10