POOLBALANCE
Keep the water clear — pool chemistry, dosing, and season-round upkeep.
From measuring your pool’s volume and dosing chlorine to balancing pH and alkalinity, sizing your pump run time, dialing in a salt system, and budgeting for heat, PoolBalance pairs free hands-on calculators with practical guides and a richly illustrated museum. Guidance you can act on, not a guess.
Pool Care Calculators
Free tools for backyard pool chemistry and upkeep — pool volume calculator, chlorine dosing calculator, pH & alkalinity balance calculator, pump run-time calculator, salt calculator, and a heater running-cost estimator.
Pool Volume Calculator
Estimate how many gallons or liters are in your pool from its shape and dimensions — rectangular, round, or oval — the starting point for every dosing calculation
Chlorine Dosing Calculator
Work out how much liquid chlorine, cal-hypo, or dichlor to add to raise your free chlorine to a target ppm, based on your pool volume and the product's strength
pH & Alkalinity Balance Calculator
Estimate how much soda ash, muriatic acid, or baking soda to add to move your pH or total alkalinity toward its target range
pH & Alkalinity Balance Order
Both readings off at once? Every pool chemical moves pH and alkalinity together, so this gives the order to add them in, what each step leaves the other reading at, and when aeration is the only thing that works
Pump Run-Time Calculator
Work out how many hours a day to run your pump for a full water turnover, from your pool volume and the pump's flow rate, plus an optional energy-cost estimate
Salt Calculator
Work out how many pounds of pool salt to add to reach your salt-water chlorinator's target ppm, from your pool volume and current reading
Pool Heater Running-Cost Estimator
Estimate the run time and fuel or electricity cost to heat your pool to a target temperature, for gas heaters, heat pumps, and resistance heaters
Pool Size Reference
Seven common pool sizes — rectangular, round, and oval — with the gallons, a chlorine dose, an alkalinity adjustment, and a pump's single-turnover run time, all derived from the same calculators used across this site
The Swimming Pool Museum
Wander an immersive museum of the pools that shaped how we swim — ancient and historic bathing places alongside the Olympic pools built for world records, the grand lidos and public baths that brought swimming to entire cities, and the hot springs and natural pools people have soaked in for millennia, each in its own gallery, so you can get to know the story behind every kind of pool: how it came to be, what makes it matter, and the role it plays in the long history of swimming.
Tour the museum →From the Journal
Fresh guides on water balance, chlorine and sanitizing, pump and filtration, salt systems, heating, and season-round maintenance, plus practical tips for keeping the water clear and the chemistry simple.
How to Calculate Your Pool's Volume (and Why It Matters)
Every dosing calculation starts with an accurate gallon count. Here's how to measure a rectangular, round, or oval pool and why the number is worth getting right.
Free Chlorine vs. Combined Chlorine: What Your Test Kit Is Really Telling You
Your test strip shows more than one chlorine number. Here's the difference between free, combined, and total chlorine, and why that harsh chemical smell means too little chlorine, not too much.
How to Balance Your Pool's pH and Total Alkalinity
pH and total alkalinity are linked, and fixing them in the wrong order leads to a frustrating chase. Here's why alkalinity comes first, and how each chemical nudges the other reading.
How Long Should You Run Your Pool Pump Each Day?
The pump is the hardest-working, most expensive-to-run piece of pool equipment. Here's how to figure out a sensible daily run time instead of guessing or running it around the clock.
Salt Water Pools Explained: How a Chlorinator Actually Works
A salt water pool isn't chlorine-free — it's still sanitized by chlorine, just generated on site. Here's how the cell works, what salt level it needs, and how to maintain it.
Gas Heater vs. Heat Pump: Choosing (and Budgeting for) Pool Heat
Gas heaters heat fast and cost more to run; heat pumps are the reverse. Here's how the two technologies actually compare, and how to estimate what heating your pool will cost either way.
Keep Learning
Plain-language explainers on chlorine chemistry, water balance, salt systems, and pool equipment, and seasoned know-how for first-time owners and long-time pool keepers alike — everything you need to keep the water clear with confidence.
Visit the Learn hub →