Browser arithmetic only; no prices, usage assumptions or external lookup. All prices use one currency. Zero is permitted where applicable. Annualization repeats the selected period.

Currency

Bath volume

Volume unit

Shower flow

Flow unit

Heat model

Bath purchased energy per use

Shower purchased energy per use

Energy unit

Density kg/L

Specific heat kJ/(kg·K)

Hot temperature

Cold temperature

Temperature unit

Efficiency (0..1]

Period days

Year days

Water price volume unit

Scenarios: one line per scenario; comma-separated columns below. No header.

Scenario, Duration minutes, Bath uses per period, Shower uses per period, Energy price per energy unit, Water price per volume unit, Wastewater price per volume unit

You supply every applicable value; results repeat those inputs and do not predict actual bills.

Enter all values and select units and models.

Scenario	Results

A QUICK WALKTHROUGH

How to use this tool

Fill every applicable field, explicitly including zero charges.
Enter one or more named scenarios using the column order shown.
Calculate and review components, differences and all equality solutions.

Units and model

Browser arithmetic only; no prices, usage assumptions or external lookup. All prices use one currency. Zero is permitted where applicable. Annualization repeats the selected period.

Results

You supply every applicable value; results repeat those inputs and do not predict actual bills.

GOOD TO KNOW

Common questions

How are assumptions chosen?

You supply every applicable value; results repeat those inputs and do not predict actual bills.

How to use this tool

Units and model

Results

Common questions

A couple more handy tools

Percentage Calculator