Construction
Concrete Volume Calculator
Rectangular pour volume from length, width, and thickness.
Free to use — no sign-up or login.
0.33 ft is about 4 inches.
Volume
ft³
Volume
yd³
Amortization schedule
| # | Date | Payment | Principal | Extra | Interest | Balance |
|---|---|---|---|---|---|---|
Rectangular volume is length × width × thickness. A 20 ft by 10 ft pad at 0.33 ft (about 4 inches) is 66.00 ft³, which is 2.44 yd³.
Round pads use the round slab calculator.
Three edges, one box
Length and width are the plan. Thickness is the depth of the pour. 0.33 ft stands in for about 4 inches.
Yards for the order
Divide cubic feet by 27. Both numbers are shown to two decimals.
Worked example: 20 by 10 ft
Length 20 ft, width 10 ft, thickness 0.33 ft. Volume 66.00 ft³ and 2.44 yd³.
\[ V = 20 \times 10 \times 0.33 \]
Frequently asked questions
What does the rectangular concrete calculator measure?
A 20 × 10 × 0.33 ft pour is 66.00 ft³.
How many decimal places does rectangular concrete calculator show?
A 20 × 10 × 0.33 ft pour is 66.00 ft³. Lengths, areas, volumes, and money use two decimals. Purchase counts are whole numbers.
Does rectangular concrete calculator include waste?
No. Add your own waste. Rebar is not subtracted or added.
Can rectangular concrete calculator mix units?
No. rectangular concrete calculator expects every input in the unit printed on its label.
Is rectangular concrete calculator a code or structural check?
No. rectangular concrete calculator is a quantity estimate. Local rules and site conditions stay outside the formula.
References
Assumptions and limitations
No waste factor and no rebar. The pour is a rectangular box.