Pool Pump Size Calculator

How It Works

Your pool pump needs to circulate all the water through the filter at least once every 8 hours (called the turnover rate). A 15,000 gallon pool needs about 31 GPM (gallons per minute) to achieve an 8-hour turnover. But bigger is not always better — an oversized pump wastes electricity, creates too much pressure on the filter, and can damage plumbing. The key is matching the pump to your plumbing diameter and total dynamic head (the resistance the pump must overcome). Variable-speed pumps are the gold standard today: they run at lower speeds most of the time, saving 50-75% on electricity while still achieving proper turnover.