Pool salt calculator
How much salt your salt cell needs, in pounds and in 40-lb bags. Enter your salt reading now and the target from your cell's manual.
- 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.
Salt by pool size
| Pool | Fresh fill to 3,200 ppm | 40-lb bags | Top-up +500 ppm |
|---|---|---|---|
| 5,000 gal (18,927 L) | 133 lb (60 kg) | 3.3 | 21 lb (9.5 kg) |
| 10,000 gal (37,854 L) | 267 lb (121 kg) | 6.7 | 42 lb (19 kg) |
| 15,000 gal (56,781 L) | 400 lb (181 kg) | 10.0 | 63 lb (29 kg) |
| 20,000 gal (75,708 L) | 534 lb (242 kg) | 13.3 | 83 lb (38 kg) |
| 25,000 gal (94,635 L) | 667 lb (303 kg) | 16.7 | 104 lb (47 kg) |
| 30,000 gal (113,562 L) | 801 lb (363 kg) | 20.0 | 125 lb (57 kg) |
Use your cell's number, not ours
Every salt cell has its own range in its manual. Trouble Free Pool's advice is to aim just above the middle of that range. Too little and the cell makes less chlorine or shuts itself off with a low-salt warning; too much is wasted salt that only leaves when you drain.
- Add salt with the cell off and the pump running. Pour it into the deep end and brush it around until it dissolves.
- Add a bag or two less than the calculator says, circulate for a day, and retest. It is easy to add more and slow to take it out.
- Before a big addition, confirm the cell's salt reading with a separate salt test.
Next: set your cell with the salt cell output calculator, and see how settings affect cell life with the run-time and lifespan calculator.
Salt dose is dimensional (8.34 lb per gallon of water). Cell targets vary by maker; follow your manual.
FAQ
How much salt do I need for my pool?
For a fresh fill to 3,200 ppm, about 267 lb (121 kg) per 10,000 gallons, which is about 6.7 bags of 40 lb. Your cell's manual gives its own target, often somewhere around 3,000–3,600 ppm; enter it in the calculator.
How many bags of salt to raise 500 ppm?
In 10,000 gallons, about 42 lb (19 kg), a little over one 40-lb bag. The calculator rounds to bags for your pool.
What kind of salt goes in a pool?
Plain sodium chloride that is at least 99% pure, with no iodine or additives. Bags sold as pool salt are made for this; if you use anything else, read the ingredients.
Should I turn off my salt cell when adding salt?
Yes. Turn the cell off, add the salt, run the pump for about a day to dissolve and mix it, retest, then turn the cell back on.
How do I lower salt in my pool?
Only by replacing water: salt does not evaporate or get used up. Replacing 20% of the water lowers salt about 20%.