Use this concrete yard calculator when you already have a volume or need to translate dimensions into the cubic yards used for many ready-mix orders. It keeps net volume distinct from an order quantity that already includes an allowance.
Start with the measurement you already have
If a supplier, plan, or earlier calculation gives you a volume, enter that value and select its unit: cubic yards, cubic feet, or cubic meters. This direct-volume path is useful when the geometry is already solved and the remaining question is conversion or ordering. If you know dimensions instead, switch to the shape path and provide the measurements there. You should not have to convert every dimension by hand before using the calculator.
A cubic yard is a volume unit, not a square yard of surface area or a linear yard of length. The exact relationships used here are 1 yd³ = 27 ft³ and 1 yd³ = 0.764554857984 m³. A surface measurement such as 400 ft² is not enough to determine cubic yards until a thickness or depth is known. The calculator labels the unit beside each input and each result so an area is not mistaken for a finished order volume.
Net volume versus the quantity to order
Net volume is the geometric amount in the measured shape before any material allowance. Order volume is net volume multiplied by one plus the allowance percentage. On a dimensions path, the default allowance is 10%, and it can be adjusted. On the direct path, choose whether the entered amount is net or already an order quantity. If it is already adjusted, the calculator must not silently add another 10%.
For example, enter 27 ft³ and mark it as an already adjusted order quantity: the result is exactly 1 yd³ and about 0.76455 m³. It should not become 1.1 yd³. If instead 27 ft³ is the net geometric volume and you intentionally apply 10%, the order quantity is 29.7 ft³, or 1.1 yd³. Keeping those two cases explicit prevents double counting when a number is passed from a slab calculator or a supplier estimate.
Convert dimensions when volume is not known
For a rectangular pour, multiply length by width by thickness after putting all three dimensions in compatible units. If length and width are in feet and thickness is in inches, divide the product by 324 to get cubic yards: yd³ = L(ft) × W(ft) × T(in) ÷ 324. The factor accounts for the thickness conversion from inches to feet and the conversion from cubic feet to cubic yards. A circular cylinder uses its measured diameter to find radius, then multiplies circular area by height.
A 10 ft by 10 ft area that is 4 in deep has volume 33.333 ft³, which is 1.23457 yd³ before allowance. With a 10% material allowance it becomes 1.35802 yd³. The area is 100 ft², but the volume is more than one cubic yard because the depth is included. If the actual pour has several sections, calculate each without overlap, add their net volumes, and apply the allowance once to the sum.
How to use the result with a supplier
The cubic-yard total gives you a quantity to discuss; it does not confirm that a supplier will deliver that exact partial amount or use a particular truck. If you expand the optional truck estimate, treat its capacity field as usable capacity supplied by you. An 8 yd³ capacity may be shown as an example, but it is not a universal truck standard. The calculator can estimate a count by rounding total order volume upward divided by the usable capacity, then show the estimated remainder for the last load.
Actual delivery scheduling depends on the supplier, mix, site access, route, timing, and local sales terms. Ask whether a minimum order, partial-load charge, mileage fee, waiting time, or pump is relevant. Those costs do not change the geometric conversion. When comparing quotes, make sure each supplier is pricing the same requested volume and that both know whether your figure includes a material allowance. For bagged products, use the bags calculator because a bag count requires a product yield, not just a volume conversion.
Ordering increments and precision
The calculator retains full precision during the conversion and rounds only for display. Small amounts should remain visible rather than being shown as zero cubic yards. If a supplier accepts orders only in increments, enter that increment only when it has been confirmed; the calculator should not assume one. An optional rounding control can show the next whole yard or another specified increment, but it must leave the unrounded requirement available for comparison.
Do not round each component before adding them. For example, separate measured pads of 0.42 yd³ and 0.42 yd³ make 0.84 yd³ net, not two independent one-yard orders. The appropriate purchase quantity depends on waste, delivery terms, placement conditions, and whether both areas are poured together. For a project with significantly different thickness zones, convert each zone separately and combine the volumes rather than applying an average depth without evidence.
Limits of a volume conversion
This tool performs unit conversion and, when requested, basic shape arithmetic. It cannot validate a plan dimension, inspect the subgrade, or decide if a slab, footing, driveway, or other structure has an appropriate design. It does not include reinforcing steel displacement, formwork geometry, pump priming, or unusual voids unless those are accounted for in the inputs. For a custom shape, use a known-volume input or divide the shape into simple non-overlapping pieces that can be measured.
Before ordering, record whether the number is net or adjusted, what unit it uses, and how it was measured. Share the dimension breakdown along with the cubic-yard result if a supplier needs to check it. If the volume came from a contractor drawing, use the drawing’s stated boundaries and units. When a price is needed, the cost-per-yard page explains a reference material range and separates it from delivery, labor, and other project charges.
Frequently asked questions
How many cubic feet are in one cubic yard?
One cubic yard equals exactly 27 cubic feet. The calculator converts without changing the physical volume; it can also show the result in cubic meters.
Does 27 cubic feet become 1.1 cubic yards with 10% waste?
Only if 27 ft³ is the net volume and you choose to add 10%. If 27 ft³ is already the order quantity, it remains 1 yd³ and receives no second allowance.
Can square feet be converted directly to cubic yards?
No. Square feet measure area. You also need thickness or depth to calculate volume before converting to cubic yards.
How many trucks will deliver my concrete?
The optional estimate divides the order volume by the usable capacity you enter and rounds up. A supplier determines actual dispatch, truck size, partial loads, and delivery arrangements.
Should I round my order to a whole cubic yard?
Only if your supplier’s ordering terms call for that increment. Keep the calculated amount visible and confirm accepted quantities, minimums, and partial-load charges directly.
Can I use this for bagged concrete?
Yes for a volume conversion, but bag counts require the selected product’s approximate yield per bag. Use the bags calculator for a product-specific count.