Gallons per Square Foot Calculator
Convert an area and depth into a water/liquid volume in gallons.
Work out how many gallons of water sit on (or are needed to flood) a given area at a chosen depth — useful for ponds, flooded slabs, irrigation and coverage estimates.
The math behind it
Volume in cubic feet = area × depth (both in feet), so depth in inches is divided by 12.
One cubic foot of water holds 7.48052 US gallons, so multiply cubic feet by 7.48052.
Worked example
100 ft² at 1 in deep → 100 × (1/12) × 7.48052 = 62.3 US gallons.
FAQ
How many gallons in a cubic foot?
7.48052 US gallons (about 28.32 liters).