Calculate Swimming Pool Water Volume
Calculate pool volume in gallons for chemical dosing, filling costs, and pump sizing. Rectangular, round, and oval pools.
Pool Volume Formula
Volume in gallons = Length × Width × Average Depth × 7.48 (for rectangular pools). A 30×15 foot pool with 5-foot average depth: 30 × 15 × 5 × 7.48 = 16,830 gallons. For round pools: π × radius² × depth × 7.48. Average depth = (shallow end + deep end) ÷ 2. Knowing your exact volume is essential for accurate chemical dosing — too little chlorine leaves the pool unsafe, too much irritates eyes and skin.
Why Pool Volume Matters
Accurate pool volume is critical for: Chemical dosing (chlorine, pH adjusters, algaecide — all calculated per gallon), pump and filter sizing (the pump should circulate the full volume in 8-12 hours), heater sizing (BTU requirements scale with volume), and water cost estimates (filling a 20,000 gallon pool costs $60-120 in most areas). Under-sizing equipment leads to poor water quality; over-sizing wastes energy.
Pool volume calculator searches peak May-August as pool owners open for summer and need to calculate chemical doses. CPC from pool supply companies (Leslie Pool, Pentair) is $3-8. Users often need repeat calculations throughout the season.
