About Pool Chem Calculators

What this site is

Pool Chem Calculators provides focused tools for common pool-care questions such as pool volume, sanitizer dosing, pH and alkalinity adjustment, salt, CYA, calcium hardness, LSI, dilution, seasonal opening and closing, and filter sizing.

The calculators use the measurements you enter together with a documented equation, product concentration, manufacturer dose table, or planning assumption. Results are estimates: real pools differ in volume, buffering, product strength, water source, equipment, weather, and bather load.

What these calculators are (and aren't)

The tools are intended to make the math transparent and repeatable. They do not replace the product label, equipment manual, local code, laboratory testing, or an on-site pool professional when a problem is unusual, severe, or safety-critical.

Where chemistry cannot be reduced safely to one universal dose, the calculator either asks for the missing input, stages the treatment, uses a clearly described planning model, or directs you to the more specific calculator.

Safety reminder: Follow the label and SDS for the product you actually use, wear the specified protective equipment, add chemicals separately, and never mix pool chemicals together.

Our calculators (how they work)

We provide focused calculators for common pool chemistry, treatment, and equipment-planning tasks:

• Pool Volume Calculator — Estimate pool gallons for chemical dosing and equipment planning
• Pool Chemical Calculator — Build a staged chlorine, pH and alkalinity plan from measured readings
• Chlorine Calculator — Dose from measured free chlorine to the operating target you choose
• pH Calculator — Estimate TA-aware doses to raise or lower pH
• Shock Calculator — Calculate a one-time treatment dose from measured FC to a selected target
• SLAM Calculator — Follow the TFP-style CYA-based algae treatment and maintenance workflow
• Pool Opening Calculator — Plan spring startup chemistry from measured readings with staged retesting
• Alkalinity Calculator — Raise TA with baking soda or stage acid-based reductions
• Salt Calculator — Calculate salt pounds and bag count for your generator target
• Stabilizer Calculator — Add CYA to a chosen target or estimate dilution when CYA is high
• CYA / FC Calculator — Reference TFP-style FC/CYA operating ratios with separate CDC baseline context
• Pool Dilution Calculator — Estimate drain/refill volume using pool and fill-water concentrations
• Muriatic Acid Calculator — Use TA-aware acid dosing to lower pH or stage alkalinity reduction
• Calcium Hardness Calculator — Raise CH or estimate fill-water-dependent dilution when CH is high
• Hot Tub Calculator — Plan spa sanitizer, pH and TA adjustments or scale a product-label dose
• LSI Calculator — Estimate calcium-carbonate saturation tendency from measured water chemistry
• Chemical Cost Calculator — Build a broad pool-chemical budget planning range

How calculations are built: simple concentration changes use mass balance and the labeled active-ingredient strength; product-specific tools scale the manufacturer's labeled dose; pH/acid tools use a simplified carbonate-buffer model that includes total alkalinity; dilution uses a fill-water-aware concentration balance; LSI uses corrected alkalinity when CYA is present. Irregular-pool volume and cost results are explicitly labeled as estimates.

Source hierarchy: sanitation and chemical-handling guidance is checked against public-health sources such as the CDC home pool and hot-tub guidance. Equipment ranges and product dose rates come from the relevant manufacturer or product label when available. Water-balance references use sources such as Taylor Technologies' Watergram guidance. When a page uses the Trouble Free Pool FC/CYA or SLAM method, it is identified as that methodology rather than presented as a universal public-health standard.

Pool-industry standards continue to evolve. The Pool & Hot Tub Alliance (PHTA) maintains current standards and codes; this site does not claim that every calculator implements every requirement of a professional standard.

How we verify calculations and sources

Pool Chem Calculators uses three broad kinds of evidence: direct concentration or mass-balance math, manufacturer-guided values such as equipment operating ranges or labeled product strengths, and planning models where real pool behavior depends on several interacting inputs.

For product- or equipment-specific claims, the exact current label or manufacturer manual takes priority over a generic rule. Public-health guidance is separated from manufacturer instructions and from community operating methods such as Trouble Free Pool's FC/CYA and SLAM approach. When a tool uses an estimate or simplified model, that limitation is stated on the page instead of being presented as a guaranteed dose.

We do not claim independent laboratory testing, hands-on testing of every product, or personal professional credentials. Page review dates indicate when the calculation method, key numerical examples, source references, and important assumptions were rechecked. Errors and source changes can be reported through the contact page.

See the full How We Verify process →

Need pool supplies?

After using our calculators to determine what your pool needs, visit our Pool Supplies page for recommended test kits, chemicals, and maintenance equipment. We've curated products commonly needed for the calculations we provide.

Privacy-first by default

All calculations run locally in your browser. The numbers you enter (pool volume, pH levels, chlorine readings) are not stored and are not transmitted to our servers.

Google Analytics is configured without client-side storage or personalized advertising signals. The site also uses a Pinterest tag for site-visit and conversion measurement; calculator inputs are not intentionally sent through that tag. See our Privacy Policy for details.

Affiliate disclosure

Pool Chem Calculators is a free resource supported by affiliate commissions. When you click product links (marked "Shop on Amazon →"), we may earn a small commission if you make a purchase. This doesn't affect the price you pay.

We only recommend products relevant to the calculations (pool chemicals, test kits, equipment). Product recommendations are based on what's needed for the specific calculator, not on commission rates.

You are never required to purchase anything. All calculators work completely free, and you can buy chemicals anywhere you prefer.

Recommended starting points

• Calculate your pool volume (needed for all other calculators)
• Plan routine chemistry from multiple readings (chlorine, pH and TA with staged retesting where needed)
• Calculate chlorine dosing (most common weekly task)
• Calculate a one-time shock treatment dose (from measured FC to the treatment target you select)
• Check overall water balance (advanced users)
• Check your CYA and chlorine targets (if pool keeps going green despite adding chlorine)

Questions or feedback?

If you have questions about our calculators, found an error, or have suggestions for improvements, please contact us. We respond to all inquiries.