Pool Chemical Dosage Calculator

Calculate the right amount of chlorine, pH adjuster, or alkalinity chemicals for your pool size. Get dosage amounts and cost estimates for each chemical type.

Pool Volume (gallons)

Current Chlorine (ppm)

Target Chlorine (ppm)

Chemical Pricing (edit to match local rates)

Liquid Chlorine ($/gal)

Granular Chlorine ($/lb)

Chlorine Tab ($/each)

Liquid Chlorine

50 oz

$1.95

Granular Chlorine

10 oz

$3.75

Chlorine Tabs (3")

2 tabs

$11.00

Purchase Option	Quantity	Est. Cost
Liquid Chlorine (12.5%)Best value	50 oz	$1.95
Granular Chlorine / Shock (Cal-Hypo)	10 oz	$3.75
Chlorine Tabs (3")	2 tabs	$11.00

Dosage recommendationTo raise chlorine by 2.5 ppm in a 20,000 gallon pool, liquid or granular chlorine can be used. Tabs are typically for ongoing maintenance, not one-time adjustments.

Test your water weeklyPool chemistry changes constantly due to sunlight, bather load, rain, and temperature. Test your water at least once per week (twice in summer) using test strips or a liquid test kit. Ideal ranges: pH 7.2–7.6, chlorine 1–3 ppm, alkalinity 80–120 ppm.

These dosages are estimates based on standard chemical concentrations. Actual dosages may vary by brand and concentration. Always follow manufacturer instructions, add chemicals gradually, and retest before adding more. Never mix chemicals together.