What size water heater do I need?
Tank gallons or tankless GPM, tuned for Utah's ~40°F incoming groundwater. We show you both side by side so you can compare.
Tank water heater
50 gallon
recommended tank size
Tankless water heater
Pick the maximum fixtures that might run at the same time:
5 GPM
recommended tankless capacity
Match: Light-duty 6.5 GPM · raw demand 3.5 GPM + 1.5 GPM headroom
How this is calculated
Tank sizing follows the peak-hour-demand model: roughly 12 gallons per person plus an 8-gallon baseline, then rounded up to the next standard tank class. High simultaneous-use households get bumped one class.
Tankless sizing sums the GPM of fixtures that might run simultaneously, then adds 1.5 GPM of headroom. Utah's incoming groundwater is around 40°F year-round in the Wasatch Front, so we target an 80°F temperature rise to 120°F. See our tankless page for more.