Pool Volume Calculator: How Many Gallons Is My Pool?
Answers: how many gallons is my pool?
Pool Desk
Covers pool and hot tub water chemistry, opening and closing. We maintain the dosing calculators and check every rate against product chemistry and public health guidance.
8 guides · 2 tools · reviewed by the Data & Methodology Desk
Our standards
- Doses are shown with the formula and the assumptions behind them.
- We never recommend mixing chemicals; each one goes into water separately.
- Test-kit accuracy limits are stated next to the result.
- We re-check guidance before each swimming season.
Sources we rely on most
- CDC Model Aquatic Health Code
- Manufacturer chemistry data (sodium chloride, calcium hypochlorite, cyanuric acid)
- University extension pool and spa guidance
How a guide gets reviewed
- 1Research. Pull the source data and extension or agency guidance.
- 2Write. Answer first, then the reasons and the steps.
- 3Figure check. An editor re-derives every number from its source.
- 4Review. The Data & Methodology Desk signs off.
- 5Re-review. Scheduled each season; changes go in the change log.
Contributors
Named contributors with verifiable credentials will be listed here. This desk publishes as an organization until then.
Tools this desk maintains
Pool Salt Calculator: How Much Salt Do I Add?
Answers: how much salt do I add?
Guides from this desk
Pool & Spa How-to
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How to Winterize a Hot Tub, and When to Keep It Running
Hot tub makers say a tub kept full, heated and covered protects itself from freezing. When to drain and winterize instead, with NOAA freeze dates and winter running costs for 21 US cities.
Pool & Spa Guide
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How Much Does It Cost to Run a Hot Tub? The Math by City
The median hot tub certified in California costs about $25 a month to keep hot at the US average electricity price. Standby cost by month for 21 cities from CEC test data, NOAA normals and EIA prices.
Pool & Spa Guide
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Hot Tub Chemical Levels: Chlorine, Bromine and pH Ranges by Source
CDC’s hot tub minimums are at least 3 ppm free chlorine or 4 ppm bromine, pH 7.0–7.8, no stabilizer and water no hotter than 104°F. Three state spa codes and three spa manuals compared, plus testing and refill schedules.
Pool & Spa Seasonal
Calculator
When to Open Your Pool: Estimated Dates for Your City and State
Open before the water warms past 60°F and after freezing nights end. Estimated opening dates for 49 cities from NOAA climate normals, and how the 70°F rule compares.
Pool & Spa Comparison
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Saltwater vs Chlorine Pool: What Changes and What It Costs
A saltwater pool is a chlorine pool: a salt cell makes the chlorine. Cell electricity and wear per gallon of liquid chlorine replaced, upkeep and corrosion from the manuals, and the stabilizer tablets add in 19 US cities.
Pool & Spa How-to
Calculator
How Much Shock to Add to a Pool: Doses, SLAM and CYA
One label shock dose adds about 5–10 ppm free chlorine. Label doses for liquid chlorine, cal-hypo, dichlor and non-chlorine shock, SLAM levels by stabilizer, and the CYA that weekly dichlor adds by city.
Pool & Spa Guide
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Ideal Pool Chemical Levels: The Ranges and Who Sets Them
Free chlorine 2–3 ppm, pH 7.4–7.6, alkalinity 80–120 ppm, calcium 200–400 ppm, stabilizer 30–50 ppm: every range tied to CDC or a manufacturer’s manual.
Pool & Spa Seasonal
When to Close Your Pool: Estimated Dates for Your City and State
Close once the water stays below 65°F, or 60°F to be safer, and before freezing nights. Estimated dates for 46 cities from NOAA climate normals.