Pool Chemical Calculators — Chlorine, pH, Salt & Shock
Calculate exact chemical amounts for crystal clear pool water.
Free tools for chlorine, pH, shock, alkalinity, and more.
No sign-ups. No stored data. Instant results.
👉 Where to start
Know your pool size? Go straight to the All-in-One Pool
Chemical Calculator — enter your test readings and get every dose at once.
Don't know your pool size? Start with the Pool Volume
Calculator — required for accurate dosing.
Have a saltwater pool? Check the Pool Salt Level Chart for your system's ideal ppm range.
Need to test first? A liquid reagent test kit gives accurate readings for all parameters.
Calculate pool chemicals for any pool type
🧪 Chlorine & shock treatment
Calculate how many chlorine tablets for your pool, liquid chlorine dosing, and shock treatment amounts for cloudy or green water
⚖️ pH & alkalinity balance
Determine muriatic acid amounts to lower pH, or how much baking soda to raise alkalinity and stabilize water chemistry
🧂 Salt water pools
Salt pool chemical calculator for proper salt levels, plus pH and alkalinity adjustments specific to saltwater systems
♨️ Spas & hot tubs
Spa chemistry calculator with dosing adjusted for smaller water volumes and higher temperatures
Essential Calculators
Most pool owners use these weekly
Pool Volume Calculator
Find your pool size in gallons — required for all other calculations
Start herePool Chemical Calculator
Chlorine, pH, alkalinity & shock doses — enter your readings once, get every dose in the correct order
All-in-oneChlorine Calculator
How much chlorine to add for safe swimming
pH Calculator
Raise or lower pH for comfort and equipment protection
Shock Calculator
Fix green or cloudy water fast
EmergencyPool Dilution Calculator
How much water to drain to lower CYA, calcium, or salt
Problem Solving
Fix algae, high CYA, and seasonal startup
SLAM Calculator
Step-by-step algae elimination using the SLAM method
Green poolCYA / FC Calculator
Find your minimum and target chlorine for your CYA level
Pool Opening Calculator
Full spring startup chemical plan in one step
Pool Winterizing Calculator
Winter closing chemicals & doses for above ground and inground pools
Common Adjustments
Balance your pool chemistry
Alkalinity Calculator
Balance total alkalinity to stabilize pH
Salt Calculator
Salt water pool chemical calculator for proper salt levels
Pool Salt Level Chart
Ideal salt ppm by system brand — Hayward, Pentair & Jandy targets, plus how to test accurately
Stabilizer Calculator
Cyanuric acid to protect chlorine from sunlight
Muriatic Acid Calculator
Calculate exact muriatic acid amounts to lower pH and alkalinity
Advanced Tools
For experienced pool owners
Need pool supplies?
Now that you know what chemicals you need, check our recommended Pool Supplies guide — test kits, chlorine, shock, pH balancers, costs, and grocery store substitutes.
🛒 Most-used: Liquid reagent test kit · Liquid chlorine · Pool shock
Pool chemistry quick tips
🎯 Test weekly
Check pH and chlorine levels at least once per week during swimming season
📐 Know your volume
Always start with an accurate pool volume measurement for precise chemical dosing
🔗 Match chlorine to your CYA
The right chlorine level depends on your stabilizer. At CYA 50 ppm, minimum FC is 4 ppm — not 1–3. Check your targets →
🔄 Balance in order
Fix alkalinity first, then pH, then chlorine — this prevents constant rebalancing
Common pool chemistry questions
How often should I test my pool water?
Test pH and chlorine at least once per week during swimming season. After heavy rain, high usage, or if the water looks cloudy, test more frequently.
What's the ideal chlorine level for a pool?
Free chlorine should be between 1–3 ppm for regular swimming. After shocking, wait until chlorine drops below 5 ppm before swimming. Note: the correct minimum depends on your CYA level — at CYA 50 ppm, minimum FC is 4 ppm, not 1 ppm. Use the CYA/FC calculator to find the right target for your stabilizer level.
Why does my pH keep rising?
High pH is often caused by low alkalinity, high pH source water, or certain sanitizers. Use the Alkalinity Calculator to stabilize pH, then adjust pH with muriatic acid if needed.
Can I add all chemicals at once?
No. Add chemicals separately, allowing the pump to circulate for at least 4 hours between additions. Never mix chemicals before adding them to the pool.
Do these calculators work for saltwater pools?
Yes. Saltwater pools still need pH, alkalinity, and stabilizer adjustments. Use the salt calculator for salt-specific dosing and the CYA/FC calculator to confirm correct chlorine targets for your stabilizer level.
What is the ideal salt level for a saltwater pool?
The ideal pool salt level is 2,700–3,400 ppm, with 3,200 ppm being the optimal target for most systems including Hayward AquaRite, Pentair IntelliChlor, and Jandy AquaPure. Below 2,700 ppm, most generators reduce or stop chlorine production. See the full pool salt level chart for brand-specific ranges and testing guidance.
Why does my pool turn green even when chlorine reads 2–3 ppm?
This is almost always a CYA problem. If your stabilizer (cyanuric acid) is above 60 ppm, a reading of 2–3 ppm FC is actually below the minimum threshold needed to prevent algae at that CYA level. Use our CYA/FC Calculator to find your correct minimum and target chlorine levels. If algae has already taken hold, use the SLAM Calculator.
How much muriatic acid do I add to my pool?
The amount depends on your pool volume and how much you need to lower pH or alkalinity. For a typical 20,000 gallon pool, 16 fl oz of muriatic acid lowers pH by approximately 0.2, or 25 fl oz lowers alkalinity by 10 ppm. Use our Muriatic Acid Calculator for exact dosing based on your specific pool size and target levels.
How many chlorine tablets does my pool need?
Most pools need 1-3 chlorine tablets per week depending on pool size, sunlight exposure, and bather load. A standard 3-inch tablet treats approximately 10,000 gallons. Use our Chlorine Calculator to determine the exact amount of chlorine tablets, liquid chlorine, or granular chlorine your pool needs to maintain 1-3 ppm free chlorine.