Tools

Free, no signup, nothing emailed to you. Each tool documents its assumptions on the page.

Calculators

Water test interpreterEnter your lab results and get each one judged against the published EPA limit, plus the treatment train your water calls for, in installation order.Softener sizing calculatorGrain capacity from hardness, iron and household size — including the iron compensation most sizing charts leave out.Salt cost calculatorAnnual salt use and cost for the softener you already own, and a warning if it is regenerating too often or too rarely.Pressure tank calculatorTank size from pump flow rate and pressure switch setting, sized to give the pump a full run cycle.Shock chlorination calculatorBleach dose from your casing size and water depth, scaled for the strength of the bleach you actually bought.

How these differ from a vendor's calculator

Most water treatment calculators are lead capture with arithmetic attached. They ask for an email before showing a result, and the result reliably recommends the product the site sells.

These do not ask for anything and are not attached to a product. Every one of them will tell you that you need nothing, if that is what your numbers say — the softener sizing tool refuses to recommend a softener at all when iron is above 3 mg/L, because at that level a softener is the wrong machine.

The arithmetic is also published rather than hidden. Every constant the tools use — the 17.1 mg/L per grain conversion, the 4 gpg of load per ppm of iron, the drawdown factors, the salt efficiency figure — is listed with its reasoning, so you can check the working or disagree with an assumption.

Every assumption, written down

Which one to start with

If you have a lab report, the water test interpreter — it reads every result at once and tells you which stages your water actually needs, in installation order. Everything else on this list answers a narrower question.

If you have no test yet, start from the symptom instead. The diagnostic pages get you to a likely cause, and that tells you what to ask the lab for.

Diagnose by symptom