Volume Calculator (Cubic Feet, Yards & Gallons)
Use this fast volume calculator to compute the exact capacity of slabs, tanks, cylinders, and bulk landscaping materials. Whether ordering ready-mix concrete, buying topsoil, or sizing a storage tank, get clean numbers in cubic feet, cubic yards, gallons, and tons instantly.
How Do You Calculate Volume?
Volume measures the three-dimensional space an object occupies. You calculate it by multiplying base area by height: Length × Width × Height for rectangles, or π × Radius² × Heightfor cylinders. Final numbers are expressed in cubic feet (ft³), cubic yards (yd³), cubic meters (m³), or liquid gallons.
When ordering materials like aggregate, soil, or gravel, volume determines your raw yardage while material density (lbs/ft³ or kg/m³) tells you total weight in short tons or metric tons. Getting these dimensions right prevents overpaying on freight or running short mid-pour.
Volume Formulas by Shape
Pick your profile below. Make sure all dimensions (radius, diameter, length, width, and depth) are converted to the same unit before running the math:
1. Rectangular Box / Slab Volume Formula
Solves space inside rectangular storage, patio slabs, footings, and garden beds.
Volume = Length × Width × Height2. Cylinder Volume Formula
Computes capacity for circular columns, sonotube footings, pipes, and round water tanks using radius (r = diameter / 2).
Volume = π × r² × h3. Sphere & Cone Formulas
Calculates dome tanks, conical hoppers, and aggregate gravel piles.
Sphere: (4/3) × π × r³ | Cone: (1/3) × π × r² × hHow to Calculate Slabs, Tanks, and Bulk Materials
How much concrete do I need for a slab calculator method: Measure the slab length and width in feet to find your total area in square feet. Convert your thickness or depth in inches to feet by dividing by 12 (for instance, a 4-inch slab is 4 / 12 = 0.333 feet). Multiply area by thickness to get cubic feet, then divide by 27 for total cubic yards. Always add 10% for spillage and sub-grade variations.
Volume calculator for cubic yards of soil/mulch/gravel: Bulk landscape suppliers sell by the cubic yard. Take your total bed square footage, multiply by target mulch depth in feet, and divide by 27. For heavy gravel or crushed stone, multiply total cubic yards by the rock density (typically 1.35 tons per yard) to order the right payload in short tons.
How to calculate volume of a rectangular tank in gallons: Calculate your internal volume in cubic feet (L × W × H). Multiply total cubic feet by 7.48052 to get US liquid gallons. If working in cubic inches, divide total volume by 231.
Volume calculator with depth in inches to cubic feet conversion: If your project area is already known in square feet, simply multiply: Area (sq ft) × [Depth (inches) / 12] = Cubic Feet. For metric users, multiply length (m) × width (m) × depth (m) to get cubic meters (m³), where 1 m³ equals 1,000 liters.
Frequently Asked Questions
How do you calculate volume?
To calculate volume, multiply the base surface area of an object by its height or depth. For a standard box or rectangular space, multiply length by width by height (Length × Width × Height). Ensure all measurements use the same unit before multiplying.
What is the formula for volume of a cylinder/box?
For a rectangular box, the formula is Volume = Length × Width × Height. For a cylinder, the formula is Volume = π × r² × h, where r is the base radius and h is the height.
How many cubic feet are in a cubic yard?
There are exactly 27 cubic feetin one cubic yard (3 ft × 3 ft × 3 ft = 27 ft³). To convert any cubic foot measurement to cubic yards, divide by 27.
How do I convert volume to weight (tons)?
Multiply total volume by material density (Volume × Density). Compacted dirt and gravel weigh around 100 to 110 lbs/ft³ (roughly 2,700 lbs per cubic yard). Divide total pounds by 2,000 for US short tons, or divide kilograms by 1,000 for metric tons.
Volume Space Calculator
1. Base Area (A_b) = π × r² = π × 5² = 78.5398 cm²
2. Volume (V) = A_b × h = 78.5398 × 12 = 942.4778 cm³
3. Lateral Surface Area (LSA) = 2πrh = 2 × π × 5 × 12 = 376.9911 cm²
4. Total Surface Area (TSA) = LSA + 2A_b = 534.0708 cm²
* Volume quantifies the 3-dimensional space occupied by a solid object. Total surface area (TSA) measures the sum of all exposed face boundaries, while capacity conversions translate cubic measures into standard liquid liters and gallons.
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