Pool Chlorine Calculator: How to Get the Exact Dose Every Time
???? Recommended Products
*As an Amazon Associate, we earn from qualifying purchases. These are products we genuinely recommend for accurate pool chlorine dosing.*
Taylor K-2006 Complete Test Kit (~$90) — The most accurate home testing kit available. Uses DPD-FAS drop testing for free and combined chlorine, plus pH, alkalinity, calcium hardness, and CYA. If you’re going to use a calculator, you need accurate inputs.
AquaChek 7-Way Test Strips (100 ct) (~$17) — Quick dip-and-read strips for daily testing. Not as precise as the Taylor kit, but great for daily spot checks between thorough tests.
In The Swim 3″ Chlorine Tablets (25 lbs) (~$70) — Trichlor slow-dissolve tablets for consistent daily chlorination. 90% available chlorine. Best price-per-pound for routine maintenance.
Champion Liquid Chlorine 4-Pack (~$40) — 12.5% sodium hypochlorite for quick-dissolve dosing and shock treatments. Doesn’t add CYA, which makes it ideal for pools that already have enough stabilizer.
In The Swim Calcium Hypochlorite Shock (24-Pack) (~$62) — 68% cal-hypo shock for weekly superchlorination. Each 1-lb bag treats up to 10,000 gallons.
—
???? Calculate It Instantly with Pool Chemical Calculator
Stop guessing with your pool chemistry! The Pool Chemical Calculator app tells you exactly how much of each chemical to add based on your pool’s size and current readings.
✅ Chlorine, pH, Alkalinity, Calcium Hardness & more
✅ Works for all pool types — chlorine, salt water, above ground
✅ Free to download
Download for Android →
Download for iPhone/iPad →
Use Online →
—
Frequently Asked Questions
How much chlorine do I add per gallon of pool water?
It depends on your current chlorine level and your target, but as a rough guide: to raise free chlorine by 1 ppm in 10,000 gallons, you need about 13 fluid ounces of liquid chlorine (12.5% concentration) or 2.5 ounces of cal-hypo granules. A pool chlorine calculator gives you the precise number for your specific pool.
How often should I add chlorine to my pool?
Most pools need chlorine added daily or every other day during swimming season. Tablet feeders provide a slow, continuous dose. If you use liquid chlorine, testing and adding every 1–2 days is typical. In hot weather or after heavy use, you may need to dose more often.
Can I just use bleach instead of pool chlorine?
Regular unscented household bleach (6% sodium hypochlorite) works in a pinch, but you’ll need more of it compared to pool-grade liquid chlorine (12.5%). A calculator can handle the conversion. Just make sure the bleach has no additives — no fragrances, no thickeners, nothing but sodium hypochlorite and water.
What’s the difference between free chlorine and total chlorine?
Free chlorine is the amount available to kill bacteria and algae right now. Combined chlorine is chlorine that’s already reacted with contaminants and is no longer effective — it’s also what causes the “chlorine smell” and eye irritation. Total chlorine is free plus combined. You always want to dose based on free chlorine.
Is there a difference between chlorine calculators for salt water pools?
Salt water pools generate chlorine through a salt cell, so you don’t add chlorine manually under normal conditions. However, you still need a calculator for shock treatments and for situations where the salt cell can’t keep up with demand — like after a party or during a heat wave.
