Calculator

Softener size calculator

People × daily gallons × hardness (gpg) × days between regenerations → rough grain capacity. Always recheck with a kit and your valve manual.

Result

Enter values and calculate

Output appears here: daily grains, capacity needed, and next common tank size.

Disclaimer

  • Starting estimate only—not a guarantee or engineering stamp.
  • Peak flow, iron bacteria, and valve type change real needs.
  • Install and main cuts may require a licensed plumber.
  • Common sizes used: 16k, 24k, 32k, 40k, 48k, 64k, 80k, 96k grains.

Formula: people × gpd × gpg × days between regenerations (optional iron adjustment). Sources and limits documented for editors in the repo tools formulas file.

Related guides & tools

essentialsHow to Choose a Water Softener (Size and Features)waterWater Hardness Explained (gpg, ppm, How to Test)startWhat Is Hard Water? (Signs, gpg, and What It Damages)systemsHow Water Softeners Work (Ion Exchange and Brine)toolsHardness unit converteressentialsFleck 5600SXT Settings: Programming Guide & Common Errors

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