Tankless Water Heater Sizing & GPM Calculator
Calculate simultaneous hot water demand (GPM), required temperature rise (°F), and minimum BTU/kW sizing for tankless heaters.
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- No signup
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Required Temp Rise (°F)
70
Peak Flow Demand (GPM)
6.5
Estimated Gas Input Required (BTU/hr)
277,439
Estimated Electric Power Required (kW)
66.7
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About Tankless Water Heater Sizing & GPM Calculator
Calculate simultaneous hot water demand (GPM), required temperature rise (°F), and minimum BTU/kW sizing for tankless heaters.
How to use Tankless Water Heater Sizing & GPM Calculator
- Enter your required input values into the fields.
- View the automatically calculated results in real time.
Key features
- Instant client-side calculation
- Real-time updates without page reloads
- Private and secure: zero data leaves your browser
Frequently asked questions
- Is this calculation free and private?
- Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.
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