🌊 Pool Salt Calculator
Enter your pool volume, current salinity, and target level to see exactly how much salt to add — in pounds, kilograms, and 40-lb bags — to keep your salt cell producing chlorine.
💧 Dial In Your Salinity
What is a Pool Salt Calculator?
It works out how many pounds of salt a saltwater pool needs to reach the salinity its chlorine generator wants. Give it your volume, the current salinity from a test strip or the cell's display, and your target, and it calculates the salt required — then converts it into kilograms and 40-lb bags.
A salt chlorine generator turns dissolved salt into chlorine, so keeping salinity in the right band is what keeps the whole system sanitising. Add salt in stages, brush it in, run the pump, and re-test — these are estimates, and it's always safer to under-add and top up than to overshoot.
❓ Frequently Asked Questions
What salinity should a saltwater pool be?
Most salt chlorine generators run best around 3,000–3,500 ppm, with 3,200 ppm a common target — that's the default here. Too little salt and the cell can't produce chlorine; too much can trigger a fault or accelerate corrosion. Always check the ideal range printed on your specific generator.
What kind of salt do I add?
Use pool-grade sodium chloride — evaporated, granulated salt that's at least 99% pure with no anti-caking agents, iodine, or additives. Avoid rock salt and water-softener pellets, which dissolve slowly and can leave residue. It usually comes in 40-lb bags, which is why the calculator gives you a bag count.
How do I add the salt?
Turn on the pump, broadcast the salt slowly across the deep end (or the shallow end of an above-ground pool), and brush it around to help it dissolve rather than piling on the floor. Run the pump for 24 hours before testing again. Add salt in stages toward the target — you can always add more, but you can only lower salinity by draining and refilling.
Will rain or splash-out change my salinity?
Yes. Salt doesn't evaporate, so it stays put as water evaporates — but heavy rain, backwashing, splash-out, and refilling all dilute it. Re-test every few weeks and top up as needed. This calculator handles a current reading, so you only ever add the difference back up to target.