Cubic Yards of Cylinder

How the volume is worked out

The volume of a cylinder is:

A worked example

Worked example. Take a cylinder with a diameter of 10 cm (so a radius of 5 cm) and a height of 25 cm. The base area is π × 5² = 78.54 cm², and multiplying by the height gives a volume of about 1.96 litres (1,963 cm³ · 0.52 US gallons).

Conversions use standard factors: 1 US gallon = 231 in³, 1 Imperial gallon = 4.54609 L, 1 litre = 1000 cm³.

Using the calculator

1. Measure across the circular end — the diameter or radius.
2. If you measured the diameter, halve it to get the radius r.
3. Square the radius and multiply by π to get the base area.
4. Multiply the base area by the height h: V = π r² h.
5. Convert the result into your preferred unit above.

Getting an accurate measurement

If you can only reach the top, measure the diameter across the opening and halve it. Keep every measurement in the same system, and let the tool convert between units for you.

What people work out next

To save you a second search, here are the related answers people most often want straight after this calculation:

Do I measure the form in feet or inches?

Either works. Enter inches if that is how the round form was measured and the tool converts to feet, then to cubic yards, before you order.

How many cubic feet is that?

One cubic yard is 27 cubic feet, and the cubic-foot value appears in the breakdown, so you can cross-check a concrete order both ways.

How much ready-mix should I order?

Round columns and footings are priced by the cubic yard; it is normal to add about 5 to 10 percent on top of the geometric figure for spillage and uneven ground.

What is it in cubic metres?

One cubic yard is about 0.765 cubic metres, shown alongside the result for metric suppliers.

What to watch out for

Two things trip people up: squaring the wrong number, and forgetting that the answer is cubic. If a result looks four times too big or too small, you have probably swapped radius and diameter somewhere, so it is always worth re-reading the measurement you are least sure of. It also helps to glance at the equivalent units; if the litre and gallon figures are both off by the same factor, the input is the culprit, not the maths.

One result, every unit

One number, many units. Whatever you enter, the result lists the same volume as litres, US gallons, Imperial gallons, millilitres, cubic centimetres, cubic inches, cubic feet, cubic yards and cubic metres at the same time. You almost never have to convert by hand: read the figure in the unit your job uses and copy any of the others straight from the breakdown. If you need a shareable version, the copy-link button preserves your exact inputs so a colleague opens the page with the same calculation already filled in.

What to work out next

Once you have your answer you may also want to work in cubic feet tank capacity gallons. These related calculators pick up where this one leaves off:

When this comes in handy

People reach for this in a range of situations:

• Ordering ready-mix for cylindrical piers
• Estimating fill for round forms
• Bulk material planning on a job site

The bottom line: with the radius or diameter and the height, the volume follows immediately, and the breakdown lets you hand the same number to anyone in the unit they prefer. Measure inside dimensions for anything that holds liquid, leave a little headspace at the top of a real container, and treat the geometric figure as a clean maximum rather than the final word on usable capacity.

Good to know