Water Softener Sizing Calculator
Static · formula-only · worked example computed when this page was built · no live data
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, regenerating every 3 days, Resin required = 96 L, Tank resin charge = 120 L, Tank diameter = 356 mm, Tank height = 1651 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. Anything the worked example does not state uses this calculator's standard default; the interactive version shows every input and lets you change it.
Worked example (Plumbing & Pumps)
Inputs: a 50-person building (6 m³/day) softening water from 250 to 50 mg/L hardness, regenerating every 3 days.
| Result | Value |
|---|---|
| Resin required | 96 L |
| Tank resin charge | 120 L |
| Tank diameter | 356 mm |
| Tank height | 1651 mm |
| Regen interval | 3 days |
Computed by WorkHive's calculation engine when this page was built; standard: WQA | NSF/ANSI 44 | PNS 1998.
How to use this calculator
- Read the worked example. It uses a 50-person building (6 m³/day) softening water from 250 to 50 mg/L hardness, regenerating every 3 days and shows every number in the method.
- Follow the formula with your own figures: it returns Resin required, Tank resin charge, Tank diameter, Tank height, Regen interval, computed per WQA | NSF/ANSI 44 | PNS 1998.
- To compute interactively, open the Water Softener Sizing Calculator inside WorkHive's free Engineering Design suite (link below). It runs the same method with your inputs.
FAQ
What is a water softener sizing calculator resin?
The Water Softener Sizing Calculator is a free online tool that 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 is free: this worked example is open to everyone, and the interactive calculator runs inside the free Engineering Design suite after a free sign-up (your work is saved to your account). 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, and a free sign-up saves your calculations, BOMs and scope-of-works to your account.