Many properly sized metered softeners regenerate roughly every several days to about a week under normal demand. Daily regeneration often suggests undersizing, extreme hardness or a programming problem; extremely long intervals can indicate oversizing or very low use.
Why regeneration frequency matters
Every regeneration uses salt and water. A unit that regenerates too frequently wastes resources and increases maintenance.
What controls the interval
Hardness, gallons used, resin capacity, reserve setting and salt dose all change the number of days between cycles.
Too frequent regeneration
If a system regenerates every day or two, verify hardness programming, household usage, leaks and usable capacity before assuming the valve is defective.
Very infrequent regeneration
Long intervals can be normal in low-use homes, but extreme oversizing can reduce the value of buying so much resin in the first place.