Water Heater Size Calculator
Determine the right water heater tank size or tankless GPM based on household size, usage patterns, and water temperatures.
Inputs
people
°F
°F
$/kWh
Results
Tank Size
75 gal
Peak Hour Demand48 gal
Tankless GPM Needed6 GPM
Temperature Rise70°F
Est. Annual Cost$996.00
How to Use This Calculator
- Enter Household Size (number of people).
- Select Peak Demand level (Low, Medium, or High simultaneous use).
- Enter Incoming Water Temp (degrees F) and Desired Hot Water Temp (degrees F).
- Input your Electricity Cost ($/kWh) or gas rate.
- Review Recommended Tank size (gallons) and the First Hour Rating needed.
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