Pool Chemical Dosing Calculator
Calculate how much chlorine and pH adjuster to add to your swimming pool to reach target water chemistry levels.
Results
What is it?
Swimming pool water chemistry requires maintaining free chlorine (sanitiser) and pH within tight ranges. This calculator estimates the weight of 65% calcium hypochlorite granules to raise chlorine levels and the weight of soda ash (raise pH) or dry acid (lower pH) needed for adjustment.
How to use
Test your pool water with a reliable test kit, enter the current and target levels for chlorine and pH, and input your pool volume. The calculator shows grams of each chemical to add. Always re-test after 4-6 hours of circulation before adding more chemicals.
Example scenario
A 50,000 L pool with chlorine at 0.5 ppm needs to reach 3.0 ppm: difference = 2.5 ppm. Chlorine granules needed = 2.5 รโ 50000 / 1000 รโ (100/65) รขโฐห 192 g. pH needs to move from 7.2 to 7.4: soda ash needed = 0.2 รโ 50000 / 1000 รโ 25 = 250 g.
Pro tip
IMPORTANT: Always add chemicals to water รขโฌโ never water to chemicals รขโฌโ to avoid dangerous splashing reactions. Pre-dissolve granules in a bucket of pool water before adding. Test and adjust one parameter at a time. Ideal ranges: Free Chlorine 2-4 ppm, pH 7.2-7.6, Total Alkalinity 80-120 ppm, Calcium Hardness 200-400 ppm. High pH dramatically reduces chlorine effectiveness.