Pick your town to fill in your water's hardness from the utility's latest report, then adjust for your household.
Estimate a water softener size for your home
How it works: grains per day = people × gallons × hardness, with 4 grains added for each ppm of iron. We size up so the softener can run on its salt-saving setting, which gives roughly three quarters of its rated capacity.
How hard is New Jersey water?
Hardness depends on where your utility gets its water. Towns on wells in limestone areas tend to have harder water than towns supplied by reservoirs. Your town's page lists the hardness from your utility's report.