Free, no signup. Water Softener Sizing Calculator.
What size water softener do I need?
Size a whole-house softener from your water hardness and household. We compensate for iron, size to a salt-efficient dose, and tell you the standard grain rating to buy -- the caveats most sizing tools skip.
10 gpgCompensated hardness
3,000 grains/dayDaily softening load
32,000-grainRecommended softener size (regenerates about every 7 days)
- We size to the RATED capacity at a salt-efficient dose (usable ~2/3 of the max rating): an oversized softener regenerates less often but wastes capacity; an undersized one runs out of soft water. The target-days input balances both.
- Iron adds ~4-5 gpg of hardness load per 1 ppm of clear-water iron, which is folded into the compensated hardness above.
- Get a real hardness number (a test kit or your utility report). A softener sized off a guess is the most common mistake.
Where to buy Search Amazon for: a whole-house water softener
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