Pool Salt Calculator (Salt Water Chlorinator)
Enter the pool volume, the current salt reading and the target from your chlorinator manual.
Your numbers
Your results
Pool Salt Calculator (Salt Water Chlorinator) by TheCalcTools
How the Pool Salt Calculator (Salt Water Chlorinator) works
Salt level in ppm is pounds of salt per million pounds of water. A US gallon of water weighs about 8.34 lb, so salt needed = (target − current) × gallons × 8.34 ÷ 1,000,000.
Add about two-thirds, let it dissolve and circulate for 24 hours, then test and top up: removing excess salt means draining water.
The formula
Worked example
Using the default values shown in the calculator:
| Pool volume (US gallons) | 15000 |
|---|---|
| Current salt level (ppm) | 1200 |
| Target salt level (ppm) | 3200 |
| Bag size (lb) | 40 |
- 15,000 gallons from 1,200 to 3,200 ppm: 250 lb (7 bags of 40 lb).
Result:
| Salt to add (lb) | 250 |
|---|---|
| Salt to add (kg) | 113.5 |
| Bags | 7 |
| If you overshoot | Only dilution lowers salt: drain part of the water and refill |
Frequently asked questions
Is a saltwater pool chlorine-free?
No. The cell makes chlorine from the salt by electrolysis.
Sources and further reading
Related calculators
More in Construction & DIY · All calculators
This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.
