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How to Add the Salt
2. Broadcast the required salt bags evenly around the deep end of the pool.
3. Use a pool brush to push the salt around until fully dissolved (usually takes 24 hours).
4. Turn the salt chlorinator back on.
Calculating exactly how much salt to add can be a frustrating guessing game. Add too little, and you have to make a second trip to the hardware store. Add too much, and the only way to fix it is to physically drain thousands of gallons of water out of your pool!
Our free Pool Salt Calculator removes the guesswork. Simply input your pool’s volume, test your current water, and enter your target parts-per-million (PPM). The tool will instantly calculate the exact weight of the salt required and tell you exactly how many standard 40-lb bags you need to buy.
Pool Salt Calculator Chart
If you don’t have time to use the exact calculator above, you can use this quick-reference chart. This table assumes your Target Salinity is 3,200 PPM and tells you exactly how many standard 40-pound bags of salt you need to buy based on your pool size and current salt level.
| Pool Volume | 0 PPM (Fresh Water) | 1,000 PPM | 1,500 PPM | 2,000 PPM | 2,500 PPM |
| 10,000 Gallons | 7 Bags | 5 Bags | 4 Bags | 3 Bags | 2 Bags |
| 15,000 Gallons | 10 Bags | 7 Bags | 6 Bags | 4 Bags | 3 Bags |
| 20,000 Gallons | 14 Bags | 10 Bags | 8 Bags | 5 Bags | 3 Bags |
| 25,000 Gallons | 17 Bags | 12 Bags | 9 Bags | 7 Bags | 4 Bags |
| 30,000 Gallons | 20 Bags | 14 Bags | 11 Bags | 8 Bags | 5 Bags |
How to Use the Pool Salt Calculator
Before you use the calculator, grab a high-quality salt test strip or take a water sample to your local pool store to find your starting baseline.
- Select Your Unit: Choose between US Gallons (which calculates salt in pounds) or Liters (which calculates salt in kilograms).
- Enter Pool Volume: Input the total volume of your swimming pool.
- Enter Current Salt Level: Input the exact PPM reading from your recent water test. When opening a freshly filled pool for the first time, your starting salt level is usually around 0 to 200 ppm (tap water contains trace amounts of salt).
- Enter Target Salt Level: Input the ideal PPM required by your specific salt cell manufacturer. For the vast majority of residential pools, the target is 3,200 ppm.
- Calculate: The tool will output the total weight required and automatically round up to tell you how many bags to purchase!
The Pool Salt Math Formula
How does our calculator determine the exact weight of salt needed? It relies on the standard physical weight of water. One gallon of water weighs approximately 8.34 pounds. The term “Parts Per Million” (PPM) literally means one millionth of that total weight.
To find the exact pounds of salt needed, we use this formula:
Pounds of Salt = Pool Volume (in gallons) × 8.34 × [ (Target PPM – Current PPM) ÷ 1,000,000 ]
Step-by-Step Example
Let’s say you have a 15,000-gallon swimming pool. You test the water in the spring and find that your current salt level is 1,500 PPM. Your Hayward chlorinator manual says your target level should be 3,200 PPM.
- Find the PPM Difference: 3,200 – 1,500 = 1,700 PPM needed.
- Calculate the Weight: 15,000 × 8.34 × (1,700 ÷ 1,000,000)
- The Result: You need exactly 212.67 pounds of salt.
- Calculate the Bags: 212.67 ÷ 40 lbs = 5.31 bags.
Because you cannot buy 0.31 of a bag, you will need to purchase 6 bags of pool salt to reach your goal safely!
Salt Water Pools vs. Traditional Chlorine Pools
Are you thinking about converting your traditional pool to salt? Here is how the two systems compare:
Salt Water Pools
Instead of buying liquid chlorine jugs or dropping harsh chlorine pucks into a floater, a saltwater pool uses a Salt Water Generator (SWG) cell. As the mildly salty water passes through the electrified cell, it automatically undergoes a chemical process called electrolysis, converting the salt directly into pure, continuous chlorine.
- Pros: Water feels softer and silkier on the skin, no harsh chemical smells, red eyes, or itchy skin. Very low day-to-day maintenance.
- Cons: The initial SWG system is expensive to install, and the electrified salt cell must be replaced every 3 to 7 years.
Traditional Chlorine Pools
You manually add store-bought chlorine directly into the water on a weekly basis to kill bacteria and algae.
- Pros: Much cheaper initial setup cost. Excellent for quickly shocking a pool that has turned green.
- Cons: High ongoing chemical costs. Chlorine levels spike and crash constantly, and the byproducts (chloramines) cause the infamous “pool smell” and skin irritation.
Ideal Salt Levels by SWG Brand
While 3,200 ppm is the golden industry standard, different Salt Water Generators have specific operating ranges. Always check your owner’s manual. Here are the target levels for the most popular brands:
| Chlorinator Brand / Model | Ideal Target Salt Level | Acceptable Operating Range |
| Hayward AquaRite | 3,200 ppm | 2,700 – 3,400 ppm |
| Pentair IntelliChlor | 3,400 ppm | 3,000 – 4,500 ppm |
| Jandy AquaPure | 3,200 ppm | 3,000 – 3,500 ppm |
| Intex Krystal Clear | 3,000 ppm | 2,500 – 3,500 ppm |
| CircuPool | 3,500 ppm | 3,000 – 4,000 ppm |
Frequently Asked Questions (FAQs)
Does salt evaporate out of the pool?
No. Salt remains in the water permanently. The only time you lose salt is through “splash-out” (kids doing cannonballs), backwashing your sand filter, or draining water during heavy rainstorms. Because of this, you usually only need to add a few bags of salt at the very beginning of the spring season.
What kind of salt should I buy?
You must buy bags specifically labeled as “Pool Salt.” This is a highly pure (99.8% or greater), finely granulated sodium chloride. Never use rock salt, ice melt, or water softener pellets. Those products contain anti-caking agents, iron, and impurities that will stain your pool plaster and ruin your expensive chlorinator cell.
Why is my calculator showing a warning to drain the pool?
If the calculator flashes a red warning, it means your “Current” salt level is already higher than your “Target” salt level! Because salt does not evaporate, the only way to lower your salt level is to physically drain water out of the pool and replace it with fresh water from a hose.
How long does it take for pool salt to dissolve?
High-quality pool salt is very fine and begins dissolving immediately. If you actively brush the bottom of the pool, you can completely dissolve a 40-pound bag in less than 15 minutes. However, it takes about 24 hours of pump circulation for the salinity to equalize perfectly across the entire pool.
Can I swim while the salt is dissolving?
Yes! In fact, swimming is one of the best ways to help mix the salt into the water. Just make sure you turn off the power to the salt chlorinator cell until the salt has fully dissolved so the cell doesn’t get hit with a highly concentrated pocket of raw salt.