Pool Salt Calculator
How much salt to add for your salt chlorine generator, at your brand's target, in stages so you don't overshoot.
Why our numbers are more realistic
The salt math is simple, and most calculators get it right. Where they go wrong is the target, and what happens after you pour.
| Typical calculator | This calculator | Why it matters |
|---|---|---|
| One target, often 3,200 ppm, for every generator | Uses your brand's range from its manual | Targets differ by brand and model. Pentair's 2017 IntelliChlor manual says 3,600 ppm ideal; Jandy's AquaPure Ei manual says 4,000; Hayward says 3,200. One 3,200 target leaves a Pentair or Jandy Ei cell short of the salt its maker asks for. |
| Rounds up to whole 40 lb bags | Shows exact pounds and where every bag would take you | A 20,000 gallon pool going from 500 to 3,200 ppm needs about 451 lb, or 11¼ bags. All 12 bags would push it to about 3,380 ppm. In a pool already near its limit, that last bag can put it over. |
| Gives one dose | Adds about 85% first, then retest after 24 hours | Too much salt can't be taken out with a chemical; the only fix is draining. Jandy's manual: "it is easier to add more if needed than it is to dilute." |
| Trusts the generator's salt display | Asks how you measured, and flags the display's error | Pentair's manual says its salt sensor reading is accurate to within ±500 ppm. That's enough to make a dose badly wrong. |
How this works
Pounds of salt = (target ppm − current ppm) ÷ 100 × 8.345 × (gallons ÷ 10,000). That's the weight of 10,000 gallons of water (83,450 lb) times 100 parts per million.
- Check against manufacturer charts: Pentair lists 300.43 lb to take 10,000 gallons from 0 to 3,600 ppm, and Jandy lists 334 lb to 4,000 ppm. Both work out to 8.35 lb per 100 ppm.
- Brand targets: the ranges in the brand list come from each maker's manual. Pentair's figures are from its 2017 IntelliChlor manual; older ones say 3,200–3,400, so check the label on your cell. Jandy's AquaPure 700/1400 manual gives only a range, so 3,200 is our pick inside it. We couldn't open CircuPool's manual to confirm its range.
- Bags: 40 lb, rounded up for buying. One bag raises 10,000 gallons by about 480 ppm.
- Staging: add about 85% first, brush, run the pump 24 hours, and retest before adding the rest. The manuals we checked don't give a share, so 85% is a planning figure: close enough to finish in one more step, with room for a test or volume error.
Common questions
What happens if I add too much salt?
You'll have to drain some water and refill; no chemical takes salt out. Enter your reading and the calculator gives the share of water to replace. Until then, expect a high-salt warning or shutdown, and very high salt can corrode equipment (Pentair flags above 4,500 ppm; Jandy warns above 4,000 ppm for AquaPure 700/1400 control centers).
Does salt evaporate?
No. Hayward's manual: "Salt is not lost due to evaporation." It leaves with splash-out, backwashing, and rain overflow, so you'll top it up now and then.
Safety
- Add chemicals to water, never water to chemicals. Never mix pool chemicals with each other.
- Follow your generator's manual. It overrides any calculator.
After you add it: order, waits and test limits
Order. Adjusting more than one thing? Do alkalinity first, then pH, then chlorine, with the pump running and at least 20 minutes between, retesting as you go. Keep calcium several hours apart from baking soda or soda ash, since together they can cloud the water. Never pour acid and chlorine in together.
| What you added | Retest after | Good to know |
|---|---|---|
| Liquid chlorine or bleach | About 30 minutes, pump on | Swim once a retest reads 4 ppm or below. |
| Cal-hypo shock | About 30 minutes for chlorine | Wait 24 hours before adjusting pH or alkalinity. Swim once a retest reads 4 ppm or below. |
| Acid (muriatic or dry) | 30 minutes to 2 hours, then the next day | pH creeps back up for a day as the water gives off carbon dioxide. Swim once a retest reads between 7.2 and 7.8. |
| Soda ash (pH up) | About 2 hours | Raises alkalinity too. |
| Baking soda | 6 to 24 hours | Run the pump at least 6 hours first. |
| Calcium chloride | 4 to 8 hours of pump time | Recheck chlorine too. |
| Salt | 24 hours, pump on | Brush the bottom so it dissolves. |
| Stabilizer (CYA) | 3 to 5 days | Don’t backwash for 48 to 72 hours. |
The short waits need the pump running; retesting the next day catches slow drift.
What your test can’t tell you.
- Most pH tests read only 6.8 to 8.2, so a reading at either end may be further out.
- Chlorine above about 10 ppm throws off the pH test and can bleach a chlorine drop test to a false low. Color-match DPD chlorine tests read only to about 5 ppm; an FAS-DPD drop test reads higher.
- Many kits can’t read stabilizer below about 20 ppm.
- Salt generator displays can be off by about 500 ppm; check with a salt test.
- Test strips read calcium only roughly; use a drop kit.
After heavy rain or an overflow, test free chlorine, pH, alkalinity and stabilizer before adding anything. Rain dilutes the water and can move pH either way, so test rather than guess. Strong sun and heat burn chlorine off faster, so in a hot, sunny climate test chlorine daily.
Filling from a well? Test the fill water at the spigot for metals first. Above about 0.2 ppm copper or 0.3 ppm iron, chlorine can turn the metals into stains. Add a metal sequestrant before you chlorinate, wait 3 to 4 days before shocking, and avoid copper-based algaecides.
From: Swim University on chemical order, Trouble Free Pool on adding chemicals, Trouble Free Pool on pH, Taylor Technologies FAQ, Swim University on metals and Trouble Free Pool on metals, plus the product labels and manuals in Sources.
What this doesn't cover
- Brand-specific shutdown levels that aren't printed in the manual, including Hayward's high-salt shutdown.
- Magnesium and mineral blends. They aren't plain sodium chloride, so dose them from the blend's own label.
- Commercial and public pools, which follow your state's health code.
Sources
- Intex CS3220 saltwater system manual: 2,500–3,500 ppm, 3,000 ideal (that model only).
- Pentair IntelliChlor manual (Rev P, 2017): 3,600 ppm ideal, 2,800–4,500 good, off below 2,600; salt chart; ±500 ppm sensor accuracy.
- Jandy AquaPure 700/1400 manual: 3.0–3.5 g/L recommended; above 4.0 g/L may damage the control center; salt chart.
- Jandy AquaPure Ei manual: 4,000 ppm recommended; "easier to add more if needed than it is to dilute."
- Hayward: how much salt does the system require?: 2,700–3,400 ppm, 3,200 optimal.
- Hayward AquaRite manual (Rev B): salt isn't lost to evaporation; the only way to lower it is to drain and refill.
Numbers last reviewed: October 9, 2026.