Pool salt calculator

Enter your pool volume, your current salt reading and your target, and this calculator tells you how many pounds of salt to add — using the standard conversion rather than a guess.

Pool volume (US gallons)

Current salt level (ppm)

Target salt level (ppm)

Add approximately 533.3 lb (241.9 kg) of pool salt to raise your salt level by 3,200 ppm.

Bag count: 14 × 40lb bags · 11 × 50lb bags · 7 × 80lb bags

Stage the dose. Add about 426.7 lb first (~80%), run the pump for 24 h, retest, then add the remainder. Never pour salt into the skimmer — broadcast it across the pool and brush until dissolved.

Add salt in stages — roughly 80% of the calculated amount, circulate, then retest before topping up.

Never add salt directly to the skimmer; broadcast it across the pool and brush until dissolved.

Why 533.3 lb? Salt dosing uses a published conversion: 1 lb of salt per 1,000 gallons raises salinity by about 120 ppm, so lb = Δppm × gallons ÷ 120,000. Source and review status.

How the calculation works

pounds of salt = (target ppm − current ppm) × gallons ÷ 120,000

The divisor comes from the industry convention that 1 lb of salt per 1,000 gallons raises salinity by about 120 ppm. We show it rather than hide it, and you can read its source and review status.

Typical salt targets

Most salt chlorinators run best between 2700–3400 ppm, and 3,200 ppm is a common target. Your equipment manual is the authority for your specific cell — check it before adjusting.

Adding salt safely

Test first. A salt test strip or meter, or your chlorinator's own reading, gives you the current ppm.
Run the pump so there is good circulation before you add anything.
Add about 80% of the calculated amount, then wait 24 h with the pump running.
Retest and add the remainder if you are still below target.
Brush the pool until the salt has dissolved — undissolved salt can stain or damage surfaces.
Never pour salt into the skimmer.

Don't know your volume? Start with the pool volume calculator — every salt calculation depends on it. We pass the result through automatically when you use the "use this volume" link.

Pool volume calculator — gallons and litres for any shape
Methodology — ppm-lb-per-gallon and salt-target-range
How to backwash a pool filter — every backwash sends water (and salt) to waste, so salinity drifts down over a season
Pool maintenance schedule — when to test salt, and everything else

Pool salt calculator

How the calculation works

Typical salt targets

Adding salt safely

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