Water & Containers

Pool Salt Calculator

Compare salt mass for a user-specified increase in concentration.

Units

Your measurements

Results update as you type.

Pool volume

Use the actual water volume, not the nominal pool size.

Current salt level (ppm)

Enter a measured salt concentration. Zero must be entered explicitly; a blank value is not treated as zero. Supported arithmetic input range only: 0–10,000 ppm, with target above current. Being within this software range does not make a target suitable or safe.

Target salt level (ppm)

Enter the target for your exact equipment and current water test. No target is selected by this calculator. Supported arithmetic input range only: 0–10,000 ppm, with target above current. Being within this software range does not make a target suitable or safe.

Bag size (optional)

Optional: enter the mass printed on the actual salt bag to see a rounded whole-bag equivalent. A blank field gives mass only.

Fractions and number formats

Use decimals (12.5), fractions (12 1/2 or 12-1/2), or explicit lengths (12ft 6in, 12′ 6″, 25 mm). A comma followed by one or two digits is a decimal comma: 12,5 = 12.5. Grouped commas mean thousands: 1,200 = 1200. Use a decimal point for ambiguous values. Scientific notation is not accepted.

Enter your measurements

Results update as you type.

About this calculator

Compare salt mass for your measured water volume and explicitly supplied concentration change. The arithmetic treats dilute-water ppm as approximately mg/L; it does not determine an equipment target or treatment procedure. Start with your own measurements, or deliberately load the labelled example.

How to use this calculator

Measure actual water volume and current salt concentration.
Enter a target justified by your exact equipment instructions.
Optionally enter the actual bag mass for a whole-bag equivalent.
Read the arithmetic comparison. Obtain product-specific advice before any addition; rounded bags are not an instruction to add every bag.

Formula

Salt kg = pool volume in litres × (target ppm − current ppm) ÷ 1,000,000

Salt lb = salt kg ÷ 0.45359237

Bags = salt mass ÷ bag mass, rounded up

Assumptions

Dilute-water concentration is approximated as 1 ppm = 1 mg/L; salt mass is water volume multiplied by the chosen concentration increase. Water-density and mixing-volume changes are not modelled.
The pool is at its normal water level; splash-out, backwash and overflow are not modelled.
Bag mass is the actual product weight, not a nominal count.
Supported arithmetic input range only: 0–10,000 ppm, with target above current. Being within this software range does not make a target suitable or safe.

Salt mass for a chosen 100 ppm increase

Salt mass for a chosen 100 ppm increase
Water volume	Salt mass
1,000 L	0.1 kg
10,000 L	1 kg
50,000 L	5 kg

Derived from dilute-water ppm ≈ mg/L. This table does not choose a target salt level.

Common mistakes

Treating a blank current concentration as a measured zero.
Choosing a target without the exact equipment instructions.
Treating a rounded whole-bag equivalent as an instruction to add all purchased salt.

Worked example

Try it: press “Load example” above the form.

Illustrative arithmetic only: 20,000 US gal and a chosen rise from 0 to 3,200 ppm correspond to about 242.266 kg (534.106 lb) of salt under the dilute-water model. With a supplied 40 lb bag size, the rounded equivalent is 14 bags; this is not an addition procedure.

Limitations

Educational salt-mass comparison only. Enter a measured starting concentration and a target from your exact equipment instructions. This tool does not select a target, prescribe an addition procedure or establish water safety.

Frequently asked questions

What target salt level should I choose?

Use the exact salt-generator instructions and a current water test. The form starts blank. The separately loaded worked example illustrates arithmetic only and does not recommend a target for your equipment.

Can this lower a pool’s salt level?

No. This model compares mass for a higher supplied concentration. Dilution or water replacement requires equipment- and site-specific qualified advice and local disposal considerations; this calculator does not prescribe it.

What does the worked example show?

Which assumptions should I check before using the result?

The arithmetic assumes a dilute-water ppm increase with no draining, overflow or other losses. Confirm the exact equipment instructions and current measurement. Dilution or water replacement requires equipment- and site-specific qualified advice and local disposal considerations; this calculator does not prescribe it.

Reviewed by Codex AI editorial agent (Editorial, 2026-11-12) · Codex independent specialist-review AI agent (educational arithmetic/source review; not licensed human approval) (Pool-chemistry, 2026-11-12).

Sources

Sources explain the methods and any named product presets. Check your product label where coverage, yield or density differs.

Hayward AquaRite100 owner manual: salt chart
Equipment-specific target guidance and approximate salt chart. This calculator uses dilute-water ppm mass balance; use your generator manual.
NIST: Revised Unit Conversion Factors
CDC: pool chemical safety
Product-specific handling and label directions; does not supply a universal chlorine target, dose procedure or safe re-entry decision.

Calculation documentation · Updated 2026-11-12 · Version 1.6.4. Estimates are planning aids. Confirm quantities, coverage and prices with your supplier before purchasing. Found an error? Report it.

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