Disclaimer — Estimates, Not Engineering

Estimates for information only

Every result produced by the calculators on this site is an estimate for informational purposes only. The sizing formula, the compensation factors and the tier mapping are industry-standard conventions — deliberately transparent, deliberately simple. They cannot see your plumbing, your exact water chemistry or your usage patterns, and they are not engineering calculations.

Before you buy or install

• Test your water. The calculators are only as good as the hardness (and iron) numbers you feed them. A test strip is a usable start; a lab test is better; a zip-code guess is what this site exists to replace.
• Verify the model. Rated capacities, iron limits and warranties are summarized here from official sources with capture dates — lineups change, so confirm the exact model number against the manufacturer's own spec sheet (linked on every brand page).
• Commercial and problem-water cases need a professional. High iron, manganese, hydrogen sulfide, tannins or sustained commercial demand change the treatment architecture, not just the size. No calculator output substitutes for licensed water treatment design.

Health note

Hard water is an aesthetic and appliance-economics issue, not a health hazard — and a softener is not a purifier. It addresses exactly one problem (hardness minerals), while drinking-water concerns (lead, nitrates, bacteria) require entirely different treatment and testing. Nothing on this site is medical or health advice.

Sources govern

Where our summary and a cited primary source disagree, the primary source wins — and we want to know (see contact). Every page carries its Last Verified date precisely because specifications drift.