Pool Water Chemistry Calculators
Dose chemicals by the numbers instead of by the bucket. Each calculator works from your pool volume, your test results and the strength of the product you actually bought.
- Pool Chlorine CalculatorDose for liquid, cal-hypo, dichlor or trichlor.
- Pool Shock CalculatorShock dose from target FC or CYA-based SLAM level.
- Pool Salt CalculatorPounds or kg of salt and number of bags.
- Pool pH CalculatorAcid or soda ash to hit your target pH.
- Pool Alkalinity CalculatorBaking soda to raise TA, acid to lower it.
- Pool Stabilizer (CYA) CalculatorStabilizer to add, or water to drain to lower CYA.
- Pool Calcium Hardness CalculatorCalcium chloride to raise CH, or drain to lower it.
- Pool LSI Calculator (Saturation Index)Is your water corrosive, balanced or scaling?
- Pool Chemical Dosage CalculatorAny common product, any change, one dose.
Which calculator do I need?
| If you want to know… | Use |
|---|---|
| How much chlorine do I add today? | Pool Chlorine Calculator |
| The pool is green or cloudy | Pool Shock Calculator |
| pH is too high or too low | Pool pH Calculator |
| pH keeps drifting | Pool Alkalinity Calculator |
| Chlorine disappears in the sun | Pool Stabilizer (CYA) Calculator |
| Setting up a saltwater system | Pool Salt Calculator |
| Etching or scale on the walls | Pool LSI Calculator (Saturation Index) |
| Plaster pool with soft water | Pool Calcium Hardness Calculator |
| Any other product and dose | Pool Chemical Dosage Calculator |
About these calculators
Balanced water comes down to a handful of numbers: free chlorine, pH, total alkalinity, calcium hardness, stabilizer (CYA) and, for saltwater pools, salt. Each calculator here turns a test result into an exact dose for your pool volume and the strength of the product you bought.
Work in a sensible order. Fix total alkalinity first, because it buffers pH. Then adjust pH, then calcium, then stabilizer, and dose chlorine last. Let each chemical circulate before you add the next, and retest rather than stacking doses.
Ideal pool chemistry levels
| Parameter | Acceptable range | Ideal |
|---|---|---|
| Free chlorine (FC) | 1–4 ppm | 2–4 ppm, or about 7.5% of CYA |
| pH | 7.2–7.8 | 7.4–7.6 |
| Total alkalinity (TA) | 60–120 ppm | 80–100 ppm (60–80 for salt pools) |
| Calcium hardness (CH) | 150–400 ppm | 250–350 ppm plaster; 150–250 ppm vinyl/fiberglass |
| Cyanuric acid (CYA) | 30–80 ppm | 30–50 ppm (chlorine); 60–80 ppm (salt) |
| Salt (SWG pools) | 2,700–3,400 ppm | 3,000–3,200 ppm (check your cell's manual) |
Residential pool targets as commonly published by the Pool & Hot Tub Alliance (ANSI/APSP/ICC-5 residential guidance) and Trouble Free Pool. pH range also matches the CDC Model Aquatic Health Code (7.2–7.8).
Tips before you start
- Test properly. A drop-based test kit (FAS-DPD for chlorine) is far more precise than strips, and precision matters when you are dosing by the ounce.
- Know your volume. Every dose scales with gallons. If your volume is a guess, every dose is a guess too.
- Safety first. Never mix chemicals, always add chemicals to water, and follow the label.