What this calculator is based on
Annual hardness load is a mass-equivalent calculation from measured hardness and water volume. It is not a prediction that all of those minerals will become scale.
EPA WaterSense's May 2026 guide says a typical softener uses about 20–70 gallons of water per regeneration, while some larger systems can use up to 200 gallons. EPA also points consumers toward demand-initiated regeneration, water efficiency of 4 gallons or less per 1,000 grains removed, and salt efficiency of at least 3,500 grains per pound. Use the exact performance data for the model and programmed salt dose you are considering.
EPA WaterSense: Soften Water Without Wasting It (May 2026) ↗ · Read the Cabo softener guide →