Cubic yards
Cylinder Volume Calculator Cubic Yards
Size up bulk volume in cubic yards for concrete, fill and large cylindrical forms, straight from feet or inches.
When you are ordering concrete or fill for a round column or footing, you think in cubic yards — and this cylinder volume calculator cubic yards gets you there. Enter the diameter and depth, and read the yd³ figure you can take to the supplier.
Because a cubic yard is 27 cubic feet, the conversion is the easy part; the care goes into measuring the round form accurately and adding a margin for waste before you place the order.
How the calculation works
- Measure across the circular end — the diameter or radius.
- If you measured the diameter, halve it to get the radius r.
- Square the radius and multiply by π to get the base area.
- Multiply the base area by the height h: V = π r² h.
- 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.
The formula behind it
The volume of a cylinder is:
V = π r² hA worked example
Worked example. Take a cylinder with a diameter of 20 cm (so a radius of 10 cm) and a height of 40 cm. The base area is π × 10² = 314.16 cm², and multiplying by the height gives a volume of about 12.57 litres (12,566 cm³ · 3.32 US gallons).
| From | To | Multiply by |
|---|---|---|
| cm³ | litres | 0.001 |
| litres | m³ | 0.001 |
| in³ | US gallons | ÷ 231 |
| ft³ | US gallons | 7.4805 |
| ft³ | litres | 28.3168 |
For anything that holds liquid, measure the inside of the cylinder — the wall takes up space that the contents cannot.
Conversions use standard factors: 1 US gallon = 231 in³, 1 Imperial gallon = 4.54609 L, 1 litre = 1000 cm³.
What people work out next
The figure above is usually the start, not the finish. These are the questions that tend to come next, answered here so you do not have to run another search:
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.
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.
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
Where people go wrong
The commonest slip is using the diameter where the formula wants the radius, which on its own quadruples the base area. Close behind is mixing units, such as a radius in centimetres with a height in metres. Keep every length in the same unit, or let the tool convert, and double-check whether you measured to the centre or across the whole width. When a figure looks surprising, that width measurement is almost always where the problem is hiding, so re-read it first.
One result, every unit
Showing every unit at once is about speed and safety: you see the answer in litres, gallons and cubic feet side by side, so there is no chance of applying the wrong conversion factor. Change the output unit at the top to make any of them the headline figure, switch the precision to exact if you want the value in terms of pi, and use copy-result to paste a tidy summary wherever you need it.
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:
To sum up, the whole job is two measurements and one formula. Enter them above, pick your unit, and you have an accurate figure plus every equivalent unit beside it. Keep a copy with the copy-result button, save the shareable link if someone else needs the same numbers, and use the history panel to compare a few options without starting from scratch.
Good to know
Is the volume of a cylinder squared or cubed?
Does this work for a tank or a pipe?
What is the formula for the volume of a cylinder?
V = π r² h — the area of the circular base (π r²) multiplied by the height (h). If you have the diameter instead of the radius, halve it first: r = d ÷ 2.