Shower Water Calculator

Calculate water and energy used for showers based on duration, flow rate, and water heating costs.

minutes
gal/min
USD/gallon

Water per Shower

20.0 gallons

Annual Shower Water7,280 gallons
Annual Heating Cost146 USD
Savings with 1.5 GPM Head58 USD

Water per Shower vs Showerhead Flow Rate

How to Calculate Shower Water Usage

Showers account for about 20% of indoor water use and are a major hot water expense.

Formula

Water per Shower = Duration (min) * Flow Rate (GPM)

Annual Water = Per Shower * Showers/Week * 52

Flow Rates

  • Standard showerhead: 2.5 GPM
  • WaterSense low-flow: 2.0 GPM
  • Ultra low-flow: 1.5 GPM
  • Rain showerhead: 2.0-2.5 GPM
  • Example Calculation

    An 8-minute shower with 2.5 GPM showerhead, 7 showers/week, $0.02/gal heating cost.

    1. 01Water per shower: 8 * 2.5 = 20 gallons
    2. 02Weekly: 20 * 7 = 140 gallons
    3. 03Annual: 140 * 52 = 7,280 gallons
    4. 04Heating cost: 7,280 * $0.02 = $146/year

    Frequently Asked Questions

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