🧪Pool Chlorine Calculator
Find how much liquid chlorine, cal-hypo or dichlor to add to reach your target chlorine.
Your pool
Not sure of your volume? Use the pool volume calculator.
Add about
51.2 fl oz
Liquid chlorine 10% to raise 20,000 gallons by 2.0 ppm
⚠️ Safety first: never mix pool chemicals together, always add chemicals to water (never water to chemicals), and follow the product label.
ppm raise
2.0
fl oz
51.2
gallons
20,000
🛒 Shopping list
- Liquid chlorine 10% (1 gal jugs)1 jugs
Add chlorine in the evening with the pump running — sunlight burns off free chlorine fast.
How it works
Amount = dose per 10,000 gallons per 1 ppm × (gallons ÷ 10,000) × ppm to raise. Typical doses: 12.8 fl oz of 10% liquid, 10.7 fl oz of 12.5% liquid, 2 oz of 65% cal-hypo, 1.8 oz of 73% cal-hypo, 2.4 oz of dichlor.
Safety: never mix chemicals, always add chemicals to water (never water to chemicals), and follow the product label.
Worked example
A 20,000 gallon pool going from 1 to 3 ppm with 10% liquid chlorine: 12.8 × 2 × 2 = 51.2 fl oz (about 0.4 gallon).
Questions people ask
Usually 1–3 ppm, higher with stabilizer (CYA).
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Last updated October 8, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.