How this salt calculator works
The estimate uses your water volume and the difference between your target and measured salt levels. It treats ppm as approximately milligrams of salt per liter of pool water for a practical residential estimate. It assumes dissolved salt, stable water volume and no water replacement during the calculation; it does not adjust for salt-product purity.
- Increase needed: target ppm minus current ppm, with zero salt addition when the target is equal to or lower than the current reading.
- US gallons: pounds of salt = gallons × ppm increase × 0.0000083454.
- Liters: kilograms of salt = liters × ppm increase ÷ 1,000,000.
- Mass conversion: 1 pound = 0.45359237 kilograms.
Results are estimates rounded to two decimal places, not a direction to add that exact amount. Add salt gradually using your manufacturer’s procedure, allow it to dissolve and circulate, and retest before adding the full estimated remaining amount. Follow the equipment manual’s circulation and generator-operation instructions rather than assuming a universal waiting time.
How to measure current salt level
Use a salinity test method suitable for your pool’s expected range, and follow its sampling, calibration and reading instructions. Enter the salt reading in ppm; a chlorine reading or total dissolved solids reading is not a substitute for a salt measurement. If the generator display and a separate reliable salt test disagree, resolve the discrepancy before adding salt.
Salinity is only one part of water care. The Pool Water Testing Guide explains the other readings to keep in view. Accurate testing and the equipment manual remain essential.
Why your chlorinator’s target range matters
Different salt chlorine generators have different documented salinity requirements. Confirm the range and target in the manual for your exact model; do not blindly copy a generic ppm value or a target from another system. Do not exceed your system’s documented salt range. This calculator uses the target you enter and cannot decide whether that target is appropriate.
Our Saltwater Pool Basics guide explains how salt chlorine generators fit into pool care. Salt concentration alone does not establish chlorine production or water safety. If chlorine is low, review the first checks for low pool chlorine instead of assuming more salt is the answer. For circulation context, see how long to run a pool pump each day; your manual determines the circulation procedure after a salt addition.
Why accurate pool volume matters
The estimated salt amount scales directly with water volume. Verify actual water capacity, including the normal waterline, before treating. Use the Pool Volume Calculator for a geometric estimate, and compare it with reliable manufacturer capacity information where available. Slopes, steps, benches and irregular shapes can affect real capacity.
What if your salt level is already too high?
If your target is at or below the measured salt level, the calculator returns zero salt to add. Adding salt cannot lower salinity. Dilution or water replacement may be required depending on your pool system and manufacturer guidance. Consult that guidance or a qualified pool professional before acting; this tool does not calculate a drain amount or provide a water-replacement procedure.
Reference and scope
The Pentair IntelliChlor owner’s guide illustrates why salt testing, mixing and equipment-specific instructions matter. Its numerical ranges and timings apply to those models, not every chlorinator. Always consult your own system’s current manual.