How do I handle dimensions in inches?

Divide each inch measurement by 12 to get feet before multiplying — for example, 18 inches is 1.5 feet.

How do I find the volume of a cylinder or round container?

Use π × radius² × height (all in feet), and remember the radius is half the width. A round tank 2 ft across has a 1-ft radius, so π × 1² × 4 (4 ft tall) ≈ 12.6 cubic feet — the common slip is to plug in the full 2 ft.

Cubic feet vs cubic yards — which do I order in?

Small amounts (bagged soil, a fish tank) are in cubic feet; bulk deliveries (gravel, concrete) are in cubic yards. 27 cubic feet make a cubic yard.

Cubic Feet Calculator

Cubic feet measure volume — length × width × height. Enter a box or space's three sides in feet for the cubic feet (and cubic yards).

Cubic feet

72cu ft

Cubic yards: 2.67 cu yd

How these numbers are worked out

The formula

Cubic feet = length × width × height, all three in feet. If any dimension is in inches, divide each one by 12 first. Cubic yards = cubic feet ÷ 27.

Constants and sources

Volume = length × width × height; 1 cubic yard = 27 cubic feet (exact).

How it was checked

Last reviewed June 16, 2026. Before this calculator was published, its formula, constants and worked example were checked in a separate, AI-assisted review that redid the arithmetic and tested the factual claims; the site owner then approved it for publishing. No engineer or tradesperson reviews these pages. Where a figure depends on the product (a density, a coverage rate, a bag size), it is either an input you can change above or a fixed planning value stated on this page, so check it against your product's label or your supplier.

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Worked example

A 6 ft × 4 ft × 3 ft space: 6 × 4 × 3 = 72 cubic feet, or 72 ÷ 27 ≈ 2.67 cubic yards.

FAQs

How do I handle dimensions in inches?: Divide each inch measurement by 12 to get feet before multiplying — for example, 18 inches is 1.5 feet.
How do I find the volume of a cylinder or round container?: Use π × radius² × height (all in feet), and remember the radius is half the width. A round tank 2 ft across has a 1-ft radius, so π × 1² × 4 (4 ft tall) ≈ 12.6 cubic feet — the common slip is to plug in the full 2 ft.
Cubic feet vs cubic yards — which do I order in?: Small amounts (bagged soil, a fish tank) are in cubic feet; bulk deliveries (gravel, concrete) are in cubic yards. 27 cubic feet make a cubic yard.