Pool Leak Detection Calculator

Leak Rate is a measurement of how fast the water LEVEL is dropping (in inches per day), independent of how large the pool is -- it comes straight from comparing your bucket and pool readings. Pool Surface Area only enters when converting that rate into an actual volume, Gallons Lost Per Day, since the same inch of drop represents far more water in a large pool than a small one.

Evaporation is naturally variable day to day -- temperature, humidity, wind, and sun exposure all shift it -- so a small difference between the pool's drop and the bucket's drop can happen even with no leak at all. This calculator only flags Leak Detected once Leak Rate clears 0.125 inches per day, a conservative buffer meant to avoid false alarms from ordinary measurement and environmental noise.

The inches you enter for Pool Water Level Drop and Bucket Water Level Drop are the total drop over however long you actually ran the test, not an automatic daily rate -- this calculator needs Test Duration to convert that total into a comparable daily figure. If you tested for 48 hours instead of the standard 24, the same total inches dropped represents half the daily rate.

A confirmed leak rate above the normal evaporation buffer means water is escaping beyond what evaporation explains -- common culprits include cracked returns, loose light fixtures, skimmer or plumbing fittings, or a crack in the shell itself. Gallons Lost Per Day gives you a sense of urgency and potential water-bill impact, but pinpointing the actual leak location usually requires a dye test at suspect fittings or a professional leak detection service.

Yes -- splashing from swimmers, backwashing the filter, topping off the pool, or running it during the test window all introduce water level changes that have nothing to do with a leak or evaporation. For an accurate reading, run the bucket test during a period when the pool isn't being used, isn't being auto-filled, and the pump/filter cycle is left in its normal running state throughout.