Pool Chemical Calculator
Turn pool volume and water test readings into planning doses for free chlorine, pH, total alkalinity, and stabilizer. Always confirm with a test kit, add chemicals separately, and retest.
For a 15,000 gallon pool going from 1 to 3 ppm free chlorine, add about 32.1 fl oz of 12.5 percent liquid chlorine, then retest.
Test readings
How to use it
- Enter pool volume. Use gallons, litres, or dimensions for a rectangular or round pool.
- Add test readings. Enter current and target free chlorine, pH, total alkalinity, and stabilizer.
- Read each dose. Use the chemical and amount shown for each positive adjustment.
- Add and retest. Add chemicals separately, circulate the pool, and confirm with a test kit before adding more.
How this works
Pool doses scale from a per-10,000-gallon table: liquid chlorine for free chlorine, soda ash or muriatic acid for pH, sodium bicarbonate for total alkalinity, and cyanuric acid for stabilizer. pH and alkalinity interact, so acid and soda ash results are guided first doses, not a license to pour everything in at once.
Sources
Volume formulas follow the Hayward chemistry quick start guide. Chemical constants are checked against Yakima County's 10,000 gallon chemical dosing chart, Champion 12.5 percent liquid chlorine dosing, Pool & Spa News soda ash guidance, and Orenda acid handling guidance.
Pool chemical questions
How much liquid chlorine raises free chlorine by 1 ppm?
This calculator uses 10.7 fl oz of 12.5 percent liquid chlorine per 10,000 gallons for each 1 ppm free chlorine increase. Scale it by your ppm change and pool volume.
Why is pH only a guided estimate?
pH dose depends on total alkalinity and buffering. The calculator gives a standard table dose, but you should add a partial dose, circulate, and retest before adding more.
How much baking soda raises alkalinity?
The calculator uses 1.5 lb sodium bicarbonate per 10,000 gallons for each 10 ppm total alkalinity increase.
How much stabilizer raises CYA?
The calculator uses 13 oz cyanuric acid per 10,000 gallons for each 10 ppm stabilizer increase. CYA dissolves slowly, so do not keep adding before the test catches up.
Can I add all chemicals at once?
No. Always confirm with a test kit, add chemicals separately with the pump running, and retest. Mixing pool chemicals directly can be dangerous.