Pool chemical dosing calculator
Enter your pool volume and where a level is now versus where you want it — get the exact amount to add. Because the point of less is more is adding the right amount, not overshooting and creating the next problem.
- Raise free chlorine 10 ppm
- ~107 fl oz liquid (12.5%) (3.3 qt; 3.2 L), ~19 oz cal-hypo (70%) (539 g), or ~22 oz dichlor (62%) (624 g)
- Raise alkalinity (TA) 10 ppm
- ~1.5 lb baking soda (680 g)
- Raise calcium (CH) 10 ppm
- ~1.2 lb calcium chloride (77% flake) (544 g)
- Raise stabilizer (CYA) 10 ppm
- ~13 oz cyanuric acid (369 g)
- Lower pH 8.0 → 7.6 (at TA 100)
- ~10 fl oz muriatic acid (1.3 cups; 296 mL), or ~0.9 lb dry acid (408 g)
Ballpark for a 10,000-gallon pool. Enter your size and levels below for your exact dose.
Example numbers are filled in so you can see an answer. Type your own over them.
Don't know your gallons? Work it out here →
Exact geometry at 7.48 gal/ft³. Kidney shapes, diving hoppers and salt/turnover figures live in the full Pool Volume Calculator.
Add chemicals safely
- Never mix pool chemicals — add one at a time.
- Always add chemical to water, never water to chemical.
- Pour slowly over a return jet with the pump running; keep it running after.
- Adjust one thing at a time and retest. Get CYA and alkalinity in range, then pH, then calcium.
- Solids (stabilizer especially) dissolve slowly — wait before retesting so you don't overshoot.
Chlorine and calcium doses are dimensional from label strength; pH doses follow Trouble Free Pool's PoolMath model. Estimates: always retest.
One chemical at a time
Each chemical also has its own page with tables and the full explanation:
- Chlorine Calculator · How much chlorine, with the target set by your CYA
- Shock (SLAM) Calculator · Your shock level by CYA, and the dose
- pH Calculator · Acid to lower pH, and how to raise it
- Alkalinity Calculator · Baking soda to raise TA, and how to lower it
- Calcium Hardness Calculator · Raise it by bag strength, or how much to drain
- CYA (Stabilizer) Calculator · Raise stabilizer, or how much water to replace
- Salt Calculator · Pounds and 40-lb bags for your salt cell
- LSI (Water Balance) Calculator · Corrosive, balanced or scaling, and the fix
- Pool Volume Calculator · Gallons for every shape
- Pool Pillow Calculator · Winter air pillow size and count, round or oval
- Pool Tracker · A free test log that judges every reading
FAQ
How much liquid chlorine do I need to raise free chlorine?
A gallon (3.8 L) of 12.5% pool chlorine raises 10,000 gallons (37,854 L) by about 12 ppm (Trouble Free Pool's figure, which allows for the strength a jug loses on the shelf); 10% raises it about 9.6 ppm. Enter your volume, current and target above for the exact amount at your chlorine strength, or use the dedicated chlorine calculator.
How much baking soda raises alkalinity?
About 1.5 lb (680 g) of baking soda raises total alkalinity by ~10 ppm in 10,000 gallons (37,854 L). The calculator scales it to your volume and target.
Why is the acid dose only an estimate?
How much acid a pH change takes depends on your alkalinity and on where your pH starts: the same 0.4 drop takes much less acid from 8.0 than from 7.6. We use the pH model from Trouble Free Pool's PoolMath, which accounts for both, but pools vary. Add about three-quarters of the estimate, run the pump, and retest before adding more, and never drop pH more than about 0.4 at once.
Which calcium chloride strength do I have?
Look at the bag. Flake is about 77%, some pellets 83–87%, and anhydrous prills 94–97%. The same rise takes about 18% less of the anhydrous kind, so pick yours in the calculator; calcium only comes back down by draining.