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Estimate the salt dose from pool volume, current ppm, target ppm, and the brand range for your salt cell.
About this calculator
Calculates the amount of pool salt needed to raise a saltwater pool from its current salinity level to a target level, based on pool volume and salt cell brand range. Supports manual volume entry or volume estimation from rectangular or round pool dimensions, with results in pounds or kilograms and bag counts for your chosen bag size.
Pool owners and maintenance professionals who manage saltwater chlorinator systems. Useful for anyone who needs to calculate exactly how much salt to add, which brand range to follow, and how many bags to purchase for the job.
Enter your pool volume manually or estimate it by selecting your pool shape (rectangle or round) and entering the dimensions. Set your current salt level in ppm, your target ppm, and the salt cell brand (Generic, Pentair, Hayward, or Jandy) to apply the recommended range. The calculator computes the salt weight needed, divides by your bag size, and shows whether the result is in range, below range, or above range.
The calculator only estimates the salt dose needed based on the ppm gap and pool volume. It does not replace a proper water test kit, chlorinator system maintenance, or manufacturer guidance. Brand ranges shown are typical values and may differ from exact specifications for your specific model. Always add salt in stages and retest after circulation to avoid overshooting.
Formula
For US gallons: salt(lbs) = volume(gal) × (targetPPM - currentPPM) / 12,000 × 1.5. For liters: salt(kg) = volume(L) × (targetPPM - currentPPM) / 1,000,000 × 1.5. The 1.5 factor accounts for the density of pool salt versus pure NaCl.
volume(gal) = length(ft) × width(ft) × averageDepth(ft) × 7.48. For liters the constant changes: volume(L) = length(m) × width(m) × averageDepth(m) × 1000. The 7.48 factor converts cubic feet to US gallons.
volume(gal) = diameter(ft)² × averageDepth(ft) × 5.9. For liters: volume(L) = diameter(m)² × averageDepth(m) × 785. These formulas assume a uniformly cylindrical pool shape.
bagsNeeded = ceil(saltWeight / bagSize). The calculator rounds up to the nearest whole bag so you never buy too little. For 40 lb bags, a 120 lb salt dose requires ceil(120 / 40) = 3 bags.
How it works
Step 1
Select Generic, Pentair, Hayward, or Jandy to use the ideal salt range for that brand. Each brand has a different recommended target range, which influences whether your current reading is in range.
Step 2
Switch to Manual Volume and enter your known pool volume, or switch to Estimate from Shape and enter your pool's length, width, and average depth for a rectangle, or diameter and depth for a round pool.
Step 3
Test your pool water and enter the current salt concentration in ppm. Set the target ppm — the calculator defaults to the midpoint of your brand's recommended range but you can adjust it manually.
Step 4
Select 40 lb or 25 kg bags to see how many bags you need. The calculator rounds up to the nearest whole bag.
Step 5
Read the salt weight needed in pounds and kilograms, the number of bags required, and the status band (In Range, Below Range, Above Range, or Drain / Refill). Toggle oversalt mode if you want to add slightly more to compensate for measurement error.
Step 6
For large salt additions, split the dose into 2–3 stages. Add one stage, let the water circulate for 4–6 hours, retest, then add more if needed. This prevents overshooting the target ppm.
Reference ranges
Recommended range is typically 2700–3400 ppm with an ideal target around 3200 ppm. Always check your specific chlorinator manual as unbranded cells vary by manufacturer.
Recommended range is 2700–3400 ppm with an ideal target of 3000–3200 ppm. Pentair IntelliChlor and IC series cells operate best within this window.
Recommended range is 2700–3400 ppm with an ideal target of 3000–3200 ppm. Hayward AquaRite and TurboCell systems use this range for optimal chlorine production.
Recommended range is 2700–3400 ppm with an ideal target of 3000–3200 ppm. Jandy AquaPure and Pro Series cells follow similar ranges to other major brands.