Volume in Cubic Feet
Last reviewed: April 2026
Calculate volume in cubic feet for boxes, rooms, containers, and shipping. Convert between cubic feet, cubic yards, cubic meters, gallons, and liters. This calculator runs entirely in your browser — your data stays private, and no account is required.
Cubic feet measure three-dimensional space using the formula length × width × height (all in feet). One cubic foot equals a box measuring 12 × 12 × 12 inches, or 1,728 cubic inches.[1] For non-rectangular shapes, different formulas apply: cylinders use πr²h, spheres use (4/3)πr³, and triangular prisms use ½ × base × height × length.[2] Volume measurements in cubic feet are essential for HVAC sizing, shipping estimates, storage unit selection, and construction material calculations — a standard 10×10 storage unit holds approximately 600-800 cubic feet of household goods.[3] Use the Cubic Yards Calculator for landscaping and concrete calculations.
Not all spaces are simple rectangles. For cylindrical containers (tanks, pipes, silos), volume = π × radius² × height — then convert from cubic inches to cubic feet by dividing by 1,728 if measurements are in inches. For irregularly shaped spaces like attics with sloped ceilings, break the space into geometric sections (rectangle + triangle) and sum the volumes. For loose materials like mulch, soil, or gravel, suppliers sell by the cubic yard (27 cubic feet). A standard wheelbarrow holds about 3 cubic feet, and a standard pickup truck bed holds 40–80 cubic feet depending on the model. Convert between volume measurements with our Volume Converter and calculate material needs with our Cubic Yards Calculator.
| Object | Dimensions (L×W×H) | Cubic Feet | Cubic Meters |
|---|---|---|---|
| Microwave | 1.5×1.5×1 ft | 2.25 | 0.064 |
| Standard refrigerator | 3×2.5×6 ft | ~18–22 | 0.51–0.62 |
| Shipping container (20 ft) | 20×8×8.5 ft | 1,360 | 38.5 |
| Moving truck (small) | 10×6×6 ft | 360 | 10.2 |
| 1 cubic yard | 3×3×3 ft | 27 | 0.76 |
Cubic feet measure three-dimensional space — the volume of a box one foot long, one foot wide, and one foot tall. While the metric system uses cubic meters and liters, cubic feet remain the standard unit for appliance sizing, shipping, storage, HVAC calculations, and construction material estimation throughout the United States.
To develop an intuitive sense for cubic footage, it helps to know common objects: a standard microwave oven interior is about 1.0–2.2 cubic feet. A full-size refrigerator holds 18–25 cubic feet. A top-load washing machine drum is 3.5–5.0 cubic feet. A standard moving box (medium, 18×18×16 inches) holds about 3 cubic feet. A cord of firewood is 128 cubic feet. A shipping container (20-foot standard) holds about 1,172 cubic feet. These benchmarks let you visualize volumes without measuring — if someone offers you "50 cubic feet of storage," you know that is about 17 medium moving boxes or two refrigerator interiors.
For rectangular spaces, the formula is straightforward: length × width × height (all in feet). When measurements are in inches, divide each dimension by 12 before multiplying, or multiply all three dimensions in inches and divide the result by 1,728 (12³). For cylindrical objects (tanks, pipes, tree trunks): volume = π × radius² × height. A cylindrical water tank 3 feet in diameter and 5 feet tall holds π × 1.5² × 5 = 35.3 cubic feet. For irregular shapes, break the space into simpler geometric forms, calculate each, and sum them. L-shaped rooms, for example, divide into two rectangles.
Key conversion factors: 1 cubic foot = 7.481 U.S. gallons (essential for water tanks and pool volumes). 1 cubic foot = 28.317 liters. 1 cubic foot = 1,728 cubic inches. 1 cubic yard = 27 cubic feet (the standard bulk material unit — soil, gravel, mulch, and concrete are sold by the cubic yard). 1 cubic meter = 35.315 cubic feet. For quick estimates: one cubic foot of water weighs about 62.4 pounds, so a 100-cubic-foot hot tub holds approximately 748 gallons weighing about 6,240 pounds — critical information for deck and floor load calculations.
Manufacturers rate appliances by interior cubic footage, making this unit essential for comparing products. Refrigerators: 10–12 cu ft for compact models, 18–22 cu ft for standard top-freezer, 22–28 cu ft for side-by-side, and 25–30 cu ft for French door models. A general guideline is 4–6 cubic feet per household member. Freezers: Upright freezers range from 5–20 cu ft; chest freezers from 5–25 cu ft. Approximately 35–40 pounds of food per cubic foot of freezer space. Washing machines: Compact (2.0–2.5 cu ft, good for 6–8 lbs of laundry), standard (3.5–4.5 cu ft, 12–16 lbs), and large capacity (5.0–6.0 cu ft, 20+ lbs). Ovens: Standard single ovens are 4.5–5.5 cu ft; double ovens provide 8–10 cu ft total. Wall oven capacity matters most when cooking for large gatherings — a turkey requires about 2.5 cubic feet of oven space.
Freight shipping charges are often based on the greater of actual weight or dimensional weight — calculated from the package's cubic dimensions. The dimensional weight formula divides cubic inches by a carrier-specific divisor (typically 139 for domestic shipments, 166 for international). A 24×18×18 inch box has 7,776 cubic inches ÷ 139 = 56 lbs dimensional weight. If the actual weight is only 30 lbs, you will be billed for 56 lbs. Optimizing packaging to minimize wasted space directly reduces shipping costs. Storage unit sizes are typically described in square feet (5×5, 10×10, 10×20) with an assumed 8-foot ceiling, making a 10×10 unit approximately 800 cubic feet of usable volume — enough for a one-bedroom apartment's contents.
HVAC systems measure airflow in cubic feet per minute (CFM). A standard residential air handling system delivers 400 CFM per ton of cooling capacity. Bathroom exhaust fans are rated at 50–110 CFM, kitchen range hoods at 100–600+ CFM, and whole-house fans at 2,000–6,000+ CFM. To calculate the required ventilation for a room, multiply the room volume in cubic feet by the desired air changes per hour (ACH) and divide by 60. A 1,500 cu ft bathroom needing 8 ACH requires 1,500 × 8 ÷ 60 = 200 CFM of exhaust capacity.
Concrete is ordered in cubic yards (1 cubic yard = 27 cubic feet), but project areas are measured in feet. A 10×12 foot patio slab, 4 inches thick, requires 10 × 12 × 0.333 = 40 cubic feet = 1.48 cubic yards of concrete. Always order 5–10% extra to account for uneven subgrade, form displacement, and spillage. Pre-mixed concrete bags (60 or 80 lb) indicate their yield in cubic feet per bag — a standard 80 lb bag yields 0.6 cubic feet, meaning the 40 cu ft patio above would need approximately 67 bags if mixing on-site. For projects over 1 cubic yard, a ready-mix truck delivery ($125–$175 per yard) is almost always more cost-effective and produces a more consistent result than hand-mixing dozens of bags. Use this calculator alongside the cubic yards calculator for bulk material projects.
Whether you are sizing an appliance, estimating shipping costs, or planning a landscaping delivery, accurate cubic footage calculations prevent costly over-ordering and frustrating shortages alike.
See also: Cubic Yards Calculator · Volume Converter · Square Footage Calculator
→ 1 cubic foot = 7.48 gallons = 28.32 liters. This conversion is essential for aquariums, hot tubs, water heaters, and any container where you need to know liquid capacity from physical dimensions.
→ Shipping uses dimensional weight, not just actual weight. Carriers charge by whichever is greater: actual weight or dimensional weight (L × W × H ÷ dimensional factor). For UPS/FedEx, the factor is 139 for domestic. A large, light package costs as much as a small, heavy one.
→ Refrigerator and freezer capacity is measured in cubic feet. A typical side-by-side fridge is 22–25 cu ft total (14–16 fridge, 7–9 freezer). French door models are 25–30 cu ft. Usable space is roughly 60–70% of rated capacity due to shelves and drawers.
→ For irregular spaces, break into rectangles. An L-shaped room is two rectangles. A room with a closet is the main room minus the closet area times ceiling height. Calculate each section separately and add. See our Cubic Yards Calculator for landscaping materials.
See also: Cubic Yards · Square Footage · Volume Converter · Area Calculator