Pool Calculators
Free pool care calculators: chlorine dosing, pH and alkalinity adjustment, pool volume, pump sizing, salt levels, and heater BTU calculations.
Volume, chemistry, pump sizing and heating. 10 calculators for pool owners. Decks, patios and surrounds sit under Construction.
Cyanuric acid (CYA) is the number to understand before touching anything else, because it is the one pool chemical you cannot remove. Stabilizer shields chlorine from sunlight, which sounds purely good until you see what it commits you to. Free chlorine then has to be held at roughly 11 to 13% of the CYA level, permanently, and the shock level scales with it too. A pool at CYA 30 clears an algae bloom at 12 ppm. The same pool at CYA 80 needs 32 ppm, which is a lot of liquid chlorine and several days of work. Overshoot and the fix is draining part of the pool and paying to refill it, so add three quarters of the calculated dose and retest.
Pump turnover works from real flow rather than the figure on the box. Manufacturer ratings assume zero head. With a filter, heater and plumbing in the way, expect 60 to 75% of it, so a pump rated at 60 gallons per minute is really moving 40 to 45.
Pool Heater BTU Sizing Calculator
Calculate BTU/hr heater needed to raise pool temperature by N degrees in a given time. Adjusts for indoor vs outdoor heat loss.
Pool Pump Turnover Time Calculator
Calculate how long your pool pump needs to run for one full water turnover and find the right daily runtime for your pump's GPM rating.
Saltwater Pool Salt Calculator
How many pounds of pool salt to add to reach target salinity for chlorinator cells. Adjusts by pool volume, current ppm, and target ppm.
Pool Cyanuric Acid (CYA / Stabilizer) Calculator
How much cyanuric acid stabilizer to add to bring pool CYA into the 30-50 ppm range (or 60-80 for saltwater chlorinator pools).
Pool Total Alkalinity Calculator (TA Adjustment)
Sodium bicarbonate dose to raise TA, or muriatic acid dose to lower TA, into the 80-120 ppm safe range for stable pool pH.
Pool pH Adjustment Calculator (Acid / Base)
Muriatic acid, dry acid, or soda ash dose to bring pool pH to the 7.4-7.6 sweet spot. Adjusted by total alkalinity for accuracy.
Pool Shock Treatment Calculator
Cal-hypo or liquid chlorine dose to shock a pool, by SLAM level for algae, breakpoint for chloramine smell, or a flat 10 ppm raise.
Pool Chlorine Dosage Calculator (FC Raise)
How much liquid chlorine, cal-hypo, dichlor, or trichlor to raise free chlorine by N ppm. Calibrated for common pool product strengths.
Pool Volume Calculator (Round / Oval)
Find gallons in a round or oval swimming pool from diameter or major and minor axes. Includes constant-slope sloped-bottom adjustment.
Pool Volume Calculator (Rectangular)
Calculate gallons in a rectangular swimming pool with sloped or flat bottom. Enter length, width, and depths to get the exact volume for chemistry math.