Pool Chemical Calculator
Turn your test results into exact chemical doses. Enter your pool volume (or dimensions), pick your chlorine type, and get step-by-step dosing for chlorine, pH, alkalinity, and CYA. Everything runs in your browser.
This free pool chemical calculator takes your pool volume and current versus target levels for chlorine, pH, total alkalinity, and cyanuric acid, then gives exact doses of liquid chlorine, bleach, dichlor, muriatic acid, baking soda, soda ash, or stabilizer, with plain-English safety steps.
Your dosing plan
Typical ranges: chlorine 1 to 3 ppm, pH 7.2 to 7.8, alkalinity 80 to 120 ppm, CYA 30 to 50 ppm. Estimates only, not professional advice. See Terms of Use.
Balancing pool chemistry: the four levels that matter and the order to fix them
Balancing pool chemistry means keeping four things in range at the same time: chlorine, pH, total alkalinity, and cyanuric acid. They interact. Chlorine kills germs and algae, but it only works well when pH sits between 7.2 and 7.8. Alkalinity acts as a buffer that keeps pH from bouncing around. Cyanuric acid shields chlorine from the sun, but too much of it locks chlorine up so it cannot sanitize.
Test first, then dose in the right order. Fix total alkalinity first, aiming for 80 to 120 ppm, then pH at 7.2 to 7.8, then chlorine at 1 to 3 ppm, and finally cyanuric acid at 30 to 50 ppm. The order matters because acid and base additions push each other around. Add one chemical, let the pump run and mix it for a few hours, retest, and only then move to the next.
The common fixes are simple. Low chlorine gets liquid chlorine or bleach. High chlorine needs nothing but time and sun. Low pH gets soda ash; high pH gets muriatic acid. Low alkalinity gets baking soda; high alkalinity gets muriatic acid followed by aeration to lift the pH back up. Low CYA gets stabilizer granules; high CYA has no chemical fix, only draining part of the pool and refilling.
The biggest mistake beginners make is dumping several chemicals in at once and guessing the doses. Measure your pool volume once, measure the water with a real test kit, and add only what the math says. Retest before swimming. Consistent small corrections beat dramatic rescues every time.
Pool chemical questions
Can I add all my pool chemicals at the same time?
No. Add one chemical at a time, let the pump run and mix it for a few hours, retest, and then move to the next. Never mix chlorine and acid together, since that can release dangerous gas. The usual order is stabilizer, chlorine, pH, then alkalinity.
How do I lower cyanuric acid (CYA) in my pool?
No chemical lowers CYA. The only fix is to drain part of the pool and refill it with fresh water. Drain the percentage your calculator shows, refill, and retest. Using less stabilized chlorine going forward keeps CYA from climbing again.
Why does my pool pH keep rising?
Aeration pushes pH up: waterfalls, fountains, spillovers, and return jets pointed at the surface all raise pH. High total alkalinity also pulls pH upward. Lower pH with muriatic acid, and if alkalinity is high, lower it too, then aerate to stabilize.
How long after adding chlorine can I swim?
Wait until the chlorine is fully mixed and the level is at or below 5 ppm, which usually takes about 30 minutes with the pump running. Retest before swimming, especially after a large dose.