Water Heater Tank Capacity Sizing Calculator
Estimate water heater gallon capacity and first-hour rating needed.
Tool inputs stay in your browser · optional AI search sends your query
Good to know: Sizes water heaters based on peak hour hot water demand to prevent running out of hot water.
How to use it (step by step)
- 1Fill in the boxes: “Number of people in household”, “Peak Morning Usage Pattern”. Example numbers are already there so you can see how it works; replace them with yours.
- 2The result updates instantly as you type (on a phone it is below the boxes).
- 3The bold line is the main answer. Tap Copy next to any value to copy it.
Words to know
No special words here. Just follow the steps. If anything is unclear, email [email protected] and we will explain it better.
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