Pool volume calculator.
Gallons plus chemical dosing - shock, chlorine, and salt - using the industry-standard formulas pool techs carry in their heads.
Your poolavg depth 5.5 ft
21,120 gallons
Shock dose (cal-hypo, routine)2.1 lb
Liquid chlorine 12.5% to raise FC 1 ppm22.6 fl oz
Salt to reach 3,200 ppm (from 0)564 lb
Minimum pump flow (8-hr turnover)44 GPM
Planning guidance using standard industry multipliers (7.5 gal/ft³ rectangular, 5.9 round/oval) and published dosing rates. Always test water before dosing and follow product labels.
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Common questions
How do I calculate pool volume in gallons?
Rectangle: L × W × average depth × 7.5. Round: diameter² × average depth × 5.9. Oval: L × W × average depth × 5.9. Average depth = (shallow + deep) ÷ 2.
How much shock do I need?
1 lb of cal-hypo per 10,000 gallons for routine shocking; double or triple for algae. Dissolve per label and run the pump.
How much salt for a saltwater pool?
~27 lb per 1,000 gallons to reach the typical 3,200 ppm target from zero. Test before the final bags - overshooting means draining.