Formula and method
Approximate pure-salt pounds = US gallons × 8.34 lb/gal × max(target ppm − current ppm, 0) ÷ 1,000,000. Divide by entered purity fraction for product mass. Whole bags round product mass up by your entered bag size.
Worked example
At 10,000 US gallons, 0 ppm measured, and a user-entered 3,200 ppm target, the estimate is 266.88 lb of pure salt using 8.34 lb/gal. This target is an example, not a universal recommendation.
Assumptions
The arithmetic uses a documented approximate water-density assumption of 8.34 lb per US gallon and treats ppm as mass fraction. Temperature, other dissolved material, salinity measurement, and pool-volume estimates affect the real result.
Important limitations
This is not chemical-treatment, chlorine, acid-dosing, or equipment advice. Verify your current salinity and the target specified for your particular salt generator before adding anything. When current ppm is at or above target, the calculated addition is zero; the tool does not advise how to lower salinity.
Frequently asked questions
Why does the result change with purity? A product below 100% salt requires more product mass to supply the same salt mass. Why are bags rounded up? It is a count of whole bags, not an instruction to pour every bag in.
Privacy
Your inputs and result stay in this browser tab. This calculator does not send entered values to a server, save them in browser storage, or put them in the URL.