Cubic Feet Calculator

Need to calculate cubic feet quickly? You're in the right place. The cubic feet calculator takes three inputs — length, width, and height — and multiplies them together to give you the total volume in ft³. It supports measurements in inches, feet, and centimeters, and even converts the result to cubic meters (m³) if you need it. Whether you're a homeowner, contractor, or shipper, this tool saves you time and eliminates calculation errors.

What is cubic foot ?

A cubic foot (ft³, also written as cu ft) is a unit of volume used in the imperial and US customary measurement systems. It represents the total three-dimensional space inside a cube where every side measures exactly 1 foot (12 inches) in length, width, and height.

Think of it as a box that is 1 foot tall, 1 foot wide, and 1 foot deep. Everything inside that box equals exactly 1 cubic foot.

Here are the key facts you should know:

• 1 cubic foot = 1 ft × 1 ft × 1 ft

• 1 cubic foot = 1,728 cubic inches (12 × 12 × 12)

• 1 cubic foot holds approximately 7.48 gallons of liquid

• 1 cubic meter (m³) = 35.315 cubic feet

Cubic feet are widely used in shipping, construction, HVAC systems, and storage calculations.

The Cubic Feet Formula

The formula to calculate cubic feet (CFT) depends on the unit of your measurements. Here are the three versions:

When Measurements Are in Feet

CFT = Length (ft) × Width (ft) × Height (ft)

When Measurements Are in Inches

CFT = [Length (in) × Width (in) × Height (in)] ÷ 1728

You divide by 1728 because 1 cubic foot equals 1,728 cubic inches.

When Measurements Are in Centimeters

CFT = [Length (cm) × Width (cm) × Height (cm)] ÷ 28316.846

You divide by 28316.846 because that's how many cubic centimeters fit inside one cubic foot.

How the Cubic Feet Calculator Works

The calculator shown has three input fields and one output field. Here's exactly what each one does:

Inputs

• Length — Enter the length of your object or space. The default unit is inches (in), but you can switch to feet or other units using the dropdown.

• Width — Enter the width. Same unit options apply.

• Height — Enter the height. Same unit options apply.

Outputs

• Volume in cubic feet — The result appears automatically in ft³ once you fill in all three dimensions.

• Volume in other units — An expandable section shows the volume converted to cubic meters (m³), giving you flexibility for international or scientific use.

The calculator handles unit conversion automatically. So even if you enter your dimensions in inches, it divides by 1728 and gives you the correct ft³ result without you doing any extra steps.

How to Calculate Cubic Feet — Step by Step

Let's walk through two practical examples so you see exactly how this works.

Example 1: Dimensions in Feet

You have a storage box that is 4 ft long, 3 ft wide, and 2 ft tall.

CFT = 4 × 3 × 2 = 24 ft³

That box takes up 24 cubic feet of space.

Example 2: Dimensions in Inches

You have a shipping carton that is 24 inches long, 18 inches wide, and 12 inches tall.

CFT = (24 × 18 × 12) ÷ 1728 CFT = 5184 ÷ 1728 = 3 ft³

That carton is exactly 3 cubic feet. If you enter these same values into the calculate cubic feet tool on CalcyMate, you'll get this result instantly without any manual division.

Cubic Feet Reference Table

Use this table to quickly look up the volume of common box sizes (dimensions in inches):

Note: All values calculated using the formula (L × W × H) ÷ 1728, where dimensions are in inches and results are in cubic feet.

Where Cubic Feet Actually Matter

You'll run into cubic feet more often than you'd think. Here are the most common real-world uses:

Shipping and freight — Carriers often charge by volume. Knowing the ft³ of your package helps you estimate costs and compare shipping options.

Construction and landscaping — When you order concrete, mulch, topsoil, or gravel, suppliers usually quote quantities in cubic feet or cubic yards. Getting this wrong means over-ordering or running short mid-project.

HVAC and air quality — Air conditioner and purifier sizing depends on the cubic footage of the room. Undersized units waste energy; oversized units cycle on and off constantly.

Moving and storage — Storage units are rented by size in cubic feet. Calculating your belongings' total volume beforehand saves you from renting a unit that's too small or too big.

Fun Fact

A standard US refrigerator holds between 18 and 26 cubic feet of space — but here's the kicker: the actual usable space is about 30–40% less once you account for shelves, drawers, walls, and door compartments. So if your fridge is listed at 22 ft³, you're probably only getting around 13–15 ft³ of actual food space. Manufacturers have been quietly "stretching" those numbers for decades! 😄

Frequently Asked Questions

What is a cubic foot?

A cubic foot (ft³) is a unit of volume equal to the space inside a cube with 1-foot sides. It equals 1,728 cubic inches or approximately 7.48 gallons. It's commonly used in shipping, construction, and storage.

How do I calculate cubic feet from inches?

Multiply your length, width, and height together in inches, then divide the result by 1,728. For example, a box that is 24 × 18 × 12 inches equals (24 × 18 × 12) ÷ 1728 = 3 ft³. The cubic to feet calculator does this automatically.

Can I calculate cubic feet from centimeters?

Yes. Multiply length × width × height in centimeters, then divide by 28,316.846. The result gives you cubic feet directly. The calculator supports this conversion natively.

What is the difference between cubic feet and cubic meters?

Cubic feet (ft³) and cubic meters (m³) both measure volume, but they use different base units. 1 cubic meter equals 35.315 cubic feet. Cubic feet are standard in the US and UK for everyday use, while cubic meters are used in most other countries and scientific contexts.

How many cubic feet are in a cubic yard?

There are 27 cubic feet in one cubic yard (3 ft × 3 ft × 3 ft = 27 ft³). This conversion is especially useful in construction when ordering materials like concrete or soil that are sold by the cubic yard.