Salt water pool calculator
Enter the pool's gallons along with the salt level you're seeing today. How many bags to get, plus how much of them goes in the water: that's what the salt water pool calculator gives you.
More tools for salt pools
- Salt level too high? Drain calculator
The portion of water you should replace.
- Cell life calculator
How many years your cell has left, figured from its hours.
- Cell size for your pool
The gallon rating worth buying, plus some buffer.
- Output % and chlorine
How much chlorine your cell makes each day.
- Check your test readings
Which numbers are off, plus what to add.
- Yearly running cost
The cell, salt top-ups and power.
Salt pounds needed for every 1,000 gallons
Aiming for 3,200 ppm (parts per million, the number a salt test shows). Then scale it by how many thousand gallons you hold.
| Your reading now | Pounds per 1,000 gal | Kilograms per 1,000 L |
|---|---|---|
| 0 ppm | 26.7 | 3.2 |
| 1,000 ppm | 18.3 | 2.2 |
| 1,500 ppm | 14.2 | 1.7 |
| 2,000 ppm | 10.0 | 1.2 |
| 2,500 ppm | 5.8 | 0.7 |
| 2,800 ppm | 3.3 | 0.4 |
| 3,000 ppm | 1.7 | 0.2 |
Chlorinator salt targets
These figures come straight from the manuals each manufacturer publishes. Aim for the figure your own manufacturer lists rather than a generic one.
| Chlorinator | Target | Band in the manual | Turns off below |
|---|---|---|---|
| Hayward AquaRite | 3,200 ppm | 2,700 to 3,400 ppm | Not given |
| Pentair IntelliChlor | 3,600 ppm | 2,800 to 4,500 ppm | 2,600 ppm |
| Pentair IntelliChlor Plus and LT | 3,600 ppm | 3,000 to 4,500 ppm | 2,600 ppm |
| Jandy AquaPure | 3,250 ppm | 3.0 to 3.5 gpl (grams per liter: 3,000 to 3,500 ppm) | 2,000 ppm |
| Jandy TruClear | 3,000 ppm | 3,000 ppm, no band | Not given |
| CircuPool | 3,500 ppm | 3,000 to 4,000 ppm | Not given |
| CircuPool SJ series | 4,000 ppm | 4,000 ppm, no band | Not given |
| Intex Krystal Clear | 3,000 ppm | 2,500 to 3,500 ppm | Not given |
| Bestway Flowclear | 3,000 ppm | 3,000 ppm, no band | Not given |
Too much salt? Figure the drain
Getting a high salt level down
The math behind the salt amount
A salt pool never burns through its salt. The cell turns the salt into chlorine, and once the chlorine has done its job it turns back into salt.
Salt only leaves when water does: splashing, backwashing, draining and rain overflow. So topping up after a wet week is to be expected, but a big drop isn't.
Questions people bring to the counter
How do I work out the salt my pool needs?
Take the target, subtract your reading, multiply that by your gallons and by 8.34, then divide by a million. The answer comes out in pounds. A pool holding 10,000 gallons needs 67 lb to climb from 2,400 to 3,200 ppm: 800 × 10,000 × 8.34 ÷ 1,000,000, so get two 40 lb bags.
For my pool, how many 40 lb salt bags are required?
Starting at zero, plan on roughly one bag for each 1,500 gallons at a 3,200 ppm target. With 15,000 gallons in the pool, ten bags does it. Got some salt in there already? Run the calculator, since a refill often means just a bag or two.
Is it possible to put in too much salt for a salt water pool?
Yes. Go past the manufacturer's upper limit and the cell may switch off; you can also start to taste the salt at roughly 3,500 to 4,000 ppm. Draining some water and refilling is the only fix. Add the salt in two halves, testing between them.
After putting salt in, how long is the wait?
Run the pump for 24 hours before you trust any fresh reading. That figure comes from both Hayward and Pentair. Sweep the pool floor during the wait; Hayward warns against letting salt collect down there.
Will rain or backwashing lower my salt?
Yes. Overflow from rain, plus backwashing and draining, all carry salt away along with the water. No salt is lost to evaporation, which means a hot dry week can't drop the level.
Should salt go in during winter?
Usually no. Cold water shuts down chlorine output on most cells: under 50 °F for a Hayward AquaRite and under 52 °F for an IntelliChlor, so any salt you add just sits there. Check the level and add more at opening time.