Water Softener Sizing Calculator
The Water Softener Sizing Calculator finds the resin volume, tank size, and regeneration interval for a hardness-removal duty. Example: for a 50-person building (6 m³/day) softening water from 250 to 50 mg/L hardness, Resin volume = 96 L, Tank diameter = 356 mm, Regen interval = 3 days (per WQA | NSF/ANSI 44 | PNS 1998).
How it works
Computed from your inputs per WQA | NSF/ANSI 44 | PNS 1998.
Worked example (Plumbing & Pumps)
Inputs: a 50-person building (6 m³/day) softening water from 250 to 50 mg/L hardness.
| Result | Value |
|---|---|
| Resin volume | 96 L |
| Tank diameter | 356 mm |
| Regen interval | 3 days |
Computed live by WorkHive's calculation engine; standard: WQA | NSF/ANSI 44 | PNS 1998.
How to use this calculator
- Enter the figures for the duty you are sizing: the worked example below uses a 50-person building (6 m³/day) softening water from 250 to 50 mg/L hardness.
- The calculator returns Resin volume, Tank diameter, Regen interval, computed per WQA | NSF/ANSI 44 | PNS 1998.
- Check the worked example to confirm the method matches how you would do it by hand, then run your own numbers in the interactive tool.
FAQ
What is a water softener sizing calculator resin?
The Water Softener Sizing Calculator is a free online tool that computes finds the resin volume, tank size, and regeneration interval for a hardness-removal duty. It shows the formula and a fully worked example so you can check the method, not just the number.
How is it calculated?
The result is computed from your inputs following WQA | NSF/ANSI 44 | PNS 1998. The worked example on this page shows a real computation with real numbers.
Is the calculator free?
Yes. WorkHive's engineering calculators are free to use, no sign-up needed for the tools. WorkHive is a free, offline-first maintenance platform built for Philippine industrial plants.
Run it on your own numbers
Open the interactive Water Softener Sizing Calculator in WorkHive: free, no sign-up needed for the calculators.