Updated September 22, 2026
Water softener sizing guides
Start with the question you need to answer. These guides explain the calculation and its limits. They are not manufacturer reviews.
- Working capacity vs advertised grain capacity — compare real salt-dose ratings with your requirement.
- Convert hardness from mg/L to GPG — check units and avoid confusing hardness with TDS.
- How iron and manganese affect the assessment — understand what the calculation includes and excludes.
- Household sizing examples — see what changes when water use or hardness changes.
Review the current product evidence before treating a catalog entry as a buying recommendation.