How to use it
- Enter the area in square feet.
- Enter the depth in feet.
- Click Calculate to see total gallons and gallons per square foot.
What it does: The tool converts a given area (sq ft) and depth (ft) into total water volume in U.S. gallons and shows the gallons needed per square foot. Why it matters: Knowing exact gallons helps you budget for irrigation, concrete, or pool filling without costly guesswork. How it works: Multiply area by depth to get cubic feet, then multiply by 7.48052 (gallons per cubic foot). The calculator does the math for you, so you only read the two results. Reading the results: Gallons = total volume you’ll need. Gallons per Square Foot = depth × 7.48052, useful for comparing different depths across the same footprint.
Pro tips
- Add a 5‑10% waste allowance for spillage or absorption.
- Round the final gallons to the nearest whole number for ordering containers.
- If ordering multiple loads, use the gallons per sq ft to verify each load’s coverage.
- Double‑check depth units; a common mistake is entering inches instead of feet.
Real-life examples
- A homeowner planning to fill a 200 sq ft patio with a 0.25 ft sand base.
- A contractor estimating concrete for a 500 sq ft slab 0.5 ft thick.
- A landscaper calculating irrigation water for a 1,000 sq ft lawn with a 0.1 ft runoff depth.
Case study
Maria needed to fill a 150 sq ft garden bed 0.3 ft deep. Using the calculator she saw she required 334 gallons total (about 2.23 gallons per sq ft), letting her order the exact amount of soil and avoid excess cost.