Pool chemistry without the math.
Enter your pool size. Get a shopping list with exact products and quantities.
Built on CDC and ANSI pool-water standards
Step 1: pool volume
Tell us your pool dimensions, save your gallons once.
Every chemistry calculator on this site needs your gallons. Calculate once, your Pool Card auto-fills the rest: chlorine, salt, pH, shock, all of it.
Calculate my pool's volume →7 pool shapes supported. Already know your gallons? Skip to all calculators →
Why volume first?
- Salt dosing depends on gallons (off by 30% if estimated)
- Chlorine dosing scales with volume. Wrong volume = wrong dose.
- Saves to your browser only. No signup. No tracking.
Or jump in by what's going on.
Or see all calculators →Just opened my pool
Chemical startup after winter
Pool is green or cloudy
Shock treatment + algae fix
Salt cell says low salt
Find out how many bags to add
Water test came back off
Fix pH, chlorine, alkalinity, or CYA
I'm a new pool owner
Start with the basics
I have an above-ground pool
Intex, Bestway, Coleman. 1,000 to 6,000 gallons.
Most used calculators
These are where most pool owners start.
Salt Calculator
Find the exact salt bags for your pool size. Enter your current level and pool volume. We tell you how many bags to buy and which brand.
Chlorine Calculator
Get the right chlorine dose, adjusted for your CYA (cyanuric acid stabilizer) level. We account for stabilizer so you do not over- or under-dose.
Spring pool season
Opening your pool this season?
Pool water looking murky after winter? Get your chemical levels right before anyone jumps in. Most pools need salt, chlorine, and a pH adjustment after sitting all winter.
Shop by what's happening
Pool owners buy in bundles. Pick the scenario that fits. Get the three things you need.
Affiliate disclosure: We may earn a commission when you buy through links on this page. Our recommendations are independent and this costs you nothing extra. Learn more›
When these picks aren't right: if your pool is on the smaller side, the bulk packaging here is typically overkill. A cheaper alternative is the smaller jug or bag at your local pool store. Only if you're running through chemicals quickly (algae recovery, hot summer week) is the larger size worth the savings vs the smaller pack.
Opening your pool
After winter, you need to shock, re-balance, and restart. Here are the three things almost every pool needs on opening day.
- Check price on Amazon →
1. Pool shock
In The Swim · Cal Hypo Shock
1 lb bags
★★★★4.4 (489) - Check price on Amazon →
2. Muriatic acid
Klean-Strip
1 gallon (14.5%)
★★★★½4.6 (1,484) - Check price on Amazon →
3. Pool salt
Morton
40 lb bag
★★★★½4.6 (1,847)
Pool went green: SOS
Algae and cloudy water. You need to shock hard, keep the chlorine high for approximately 48 hours, and stabilize so it doesn't happen again.
- Check price on Amazon →
1. Pool shock
In The Swim · Cal Hypo Shock
1 lb bags
★★★★4.4 (489) - Check price on Amazon →
2. Liquid chlorine
Champion · Liquid Chlorine
1 gal jug (12.5%)
★★★★4.3 (612) - Check price on Amazon →
3. CYA / stabilizer
In The Swim · Stabilizer
4 lb container
★★★★4.4 (697)
Weekly maintenance supplies
The three chemicals most pool owners typically top up every 1–2 weeks in season (per typical residential pool maintenance cadence). Build a quarter's supply in one order.
- Check price on Amazon →
1. Liquid chlorine
Champion · Liquid Chlorine
1 gal jug (12.5%)
★★★★4.3 (612) - Check price on Amazon →
2. Muriatic acid (pH down)
Klean-Strip
1 gallon (14.5%)
★★★★½4.6 (1,484) - Check price on Amazon →
3. Baking soda (alkalinity up)
Arm & Hammer
4 lb box
★★★★½4.7 (2,856)
Fix it yourself
Step-by-step pool care guides from opening day to winterizing.
How to Open a Pool
SpringStep-by-step startup checklist with chemical dosing for opening season.
How to Fix a Green Pool
SummerIdentify the cause and clear a green pool fast with the right shock and algaecide.
How to Close a Pool
FallWinterize correctly to avoid freeze damage and a clean opening next spring.
Pool Chemistry Basics
Year-roundThe essentials: FC, pH, TA, CYA, and calcium. What they do and why they matter.
Know your pool shape? Start with volume.
Why pool owners trust our calculators
Verified formulas
In our view, the CDC pool-water standards and the ANSI pool-water standard are the only formula sources worth trusting for residential pool dosing. Every calculation here traces to one of them. No guesswork.
Real purchase units
We tell you how many bags or bottles to buy. Walk into the store knowing exactly what you need.
Free, always
No login, no paywall. We recommend the exact products for your pool and earn a commission if you buy through our links.
Pool chemistry at a glance
Every target range on one card. Sourced from CDC pool-water standards and ANSI pool-industry standards.
Free Chlorine (FC)
1–4 ppm
Kills bacteria and algae. Lower = unsafe. Higher = burns eyes and fades swimsuits.
Chlorine calculator →pH
7.2–7.8
How acidic the water is. High pH makes chlorine ineffective. Low pH corrodes plaster and metals.
pH calculator →Total Alkalinity (TA)
80–120 ppm
Buffers pH. Low TA = pH bouncing everywhere. Fix TA first, then pH.
Alkalinity calculator →Cyanuric Acid (CYA)
30–50 ppm
Sunscreen for chlorine. Too little = chlorine burns off in hours. Too much = chlorine can't kill algae.
CYA calculator →Calcium Hardness
200–400 ppm
Prevents plaster etching and metal corrosion. Soft water eats your pool.
Calcium calculator →Salt (SWG pools)
2,700–3,400 ppm
Food for the salt cell. Below = cell won't produce chlorine. Above = cell damage + warranty void.
Salt calculator →