Cubic Feet Calculator
Calculate volume in cubic feet (cu ft), cubic yards, gallons, and liters for any 3D shape or space. Explore interactive 2D blueprint diagrams, 360° 3D orbit visualizers, multi-unit conversions, and step-by-step geometric math.
Choose Shape or Object Type
Dynamic vector diagram reflects dimension inputs in real time.
Enter Dimensions (ft)
Support decimals & fractionsV = Length × Width × Height
How Big is 320 cu ft in Real Life?
How to Calculate Cubic Feet & Volume
Cubic feet (expressed as cu ft or ft³) measures three-dimensional space and capacity. One cubic foot equals the volume of a physical cube measuring exactly 1 foot (12 inches) on length, width, and height (1 ft × 1 ft × 1 ft = 1 cu ft = 1,728 cu in).
- Rectangular Box / Tank: Volume = Length × Width × Height (V = L × W × H).
- Cube: Volume = Edge³ (V = a³).
- Cylinder: Volume = π × r² × h (where r is radius and h is height).
- Cone: Volume = ⅓ × π × r² × h.
- Sphere: Volume = ⁴⁄₃ × π × r³.
- Capsule: Volume = π × r² × h_cyl + ⁴⁄₃ × π × r³.
- Conical Frustum: Volume = ⅓ × π × h × (r₁² + r₂² + r₁r₂).
- Square Pyramid: Volume = ⅓ × Base Area × Height = ⅓ × a² × h.
- Hollow Tube / Pipe: Volume = (π / 4) × (d_outer² - d_inner²) × L.
Key 3D Geometric Principles & Volume Rules
Fundamental principles and practical calculation shortcuts:
- Cubic Scaling Law (k³): If you double every dimension of a 3D container (2× length, 2× width, 2× height), its surface area quadruples (2² = 4×), but its volume capacity multiplies by eight (2³ = 8× or 800%).
- Cubic Yards in Bulk Materials: Concrete, garden soil, gravel, and mulch are universally ordered by the Cubic Yard (yd³). To convert cubic feet to cubic yards, divide by 27 (1 cu yd = 27 cu ft = 3 ft × 3 ft × 3 ft).
- Water Capacity & Weight: 1 cubic foot of water equals approximately 7.48 US liquid gallons (28.32 Liters) and weighs approximately 62.4 lbs (28.3 kg).
- Cavalieri's Principle: Two 3D solids of equal height have equal volumes if their cross-sectional areas at all intermediate heights are equal.
Everyday Relatable Volume Benchmarks
Reference dimensions and cubic capacities for common household and construction items:
| Item / Structure | Typical Dimensions | Volume (Cubic Feet) | Metric / Capacity |
|---|---|---|---|
| Standard Microwave | 1.5 × 1.2 × 1.0 ft | 1.2 – 1.8 cu ft | 34 – 51 Liters |
| Kitchen Refrigerator | 3.0 × 2.8 × 5.8 ft | 18 – 26 cu ft | 510 – 736 Liters |
| Washing Machine Drum | 1.8 ft diam × 1.8 ft depth | 4.5 – 5.2 cu ft | 127 – 147 Liters |
| Raised Garden Bed (4x8x1 ft) | 8.0 × 4.0 × 1.0 ft | 32 cu ft (1.19 cu yd) | 906 Liters |
| Standard Pickup Truck Bed | 6.5 × 5.5 × 1.8 ft | 64 – 75 cu ft | 2.4 – 2.8 cu yd |
| Transit Concrete Mixer Truck | Full transit drum | 216 – 270 cu ft | 8 – 10 cu yd |
| 20ft ISO Shipping Container | 19.4 × 7.7 × 7.8 ft (inner) | 1,170 cu ft | 33.2 m³ (43.3 cu yd) |
| Standard Swimming Pool (15x30x5 ft) | 30 × 15 × 5.0 ft avg depth | 2,250 cu ft | 16,830 US Gallons |
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Frequently Asked Questions
To calculate cubic feet for a rectangular box or room, measure the length, width, and height in feet, then multiply them together: Volume = Length × Width × Height. If your measurements are in inches, multiply Length × Width × Height in inches and divide by 1,728 (since 1 cu ft = 1,728 cu in).
To convert cubic feet to cubic yards, divide the total cubic feet by 27 (1 cubic yard = 27 cubic feet = 3 ft × 3 ft × 3 ft). For example, 135 cubic feet equals exactly 5 cubic yards (135 ÷ 27 = 5 cu yd).
One cubic foot equals approximately 7.48052 US liquid gallons (or 28.3168 Liters). If you have a 100 cu ft water tank, it holds approximately 748 US gallons.
The volume of a cylinder is calculated using the formula: Volume = π × r² × h, where r is the radius (half the diameter) and h is the height or depth in feet. For example, a round tank with 4 ft radius and 6 ft height has a volume of π × 4² × 6 ≈ 301.59 cubic feet.
Yes! The calculator supports compound feet and inches (e.g., 10' 6", 12 ft 4 in), standard fractions (e.g., 5 1/2, 3/4), decimals, and metric units (meters, cm, mm) with automatic real-time conversion.
This tool supports 12+ geometric solids: Rectangular Box/Tank, Cube, Cylinder, Cone, Sphere, Capsule, Conical Frustum (truncated cone), Square Pyramid, Spherical Cap (dome), Ellipsoid, Hollow Tube/Pipe, Triangular Prism, and Trapezoidal Prism.
Yes! The calculator, interactive 2D blueprints, and 3D spatial orbit canvas visualizer run 100% locally in your web browser with zero external server dependencies, ensuring full offline functionality and complete data privacy.