How to use the concrete yard calculator
- Choose what you know. Pick length, width and thickness, or square feet and thickness, or convert a volume you already have in cubic feet or cubic metres.
- Enter the numbers. Type each number and choose its unit. Set the waste allowance, or set it to 0 for the exact volume.
- Read the cubic yards. The result shows the cubic yards to order, the same amount rounded up to a quarter yard, and the volume in cubic feet and cubic metres.
What is a yard of concrete?
A yard of concrete is one cubic yard: a volume 3 feet long, 3 feet wide and 3 feet high. It equals 27 cubic feet, or about 0.76 cubic metres. Ready-mix concrete in the United States is ordered by the cubic yard, so suppliers and contractors say "yards" for short.
A concrete yard calculator is a tool that converts the size of a pour into cubic yards. It is also called a concrete yardage calculator.
Features
- Cubic yards from length, width and thickness
- Cubic yards from square feet and thickness
- A converter from cubic feet or cubic metres to cubic yards
- The order amount rounded up to the next quarter yard
- An adjustable waste allowance
- A cost from your own price per cubic yard
- A live 3D preview, a PDF of the estimate and a WhatsApp share button
What you can use it for
- Ordering ready-mix concrete from a truck, which is sold by the cubic yard
- Checking a contractor's quote for a slab, a driveway or a foundation
- Turning square feet and a thickness into cubic yards
- Converting cubic feet or cubic metres into cubic yards
How to calculate yards of concrete
Cubic yards = length (ft) × width (ft) × thickness (ft) ÷ 27.
If you know the area: cubic yards = area (sq ft) × thickness (in) ÷ 12 ÷ 27, which is the same as area × thickness in inches ÷ 324.
Worked example: a 20 ft by 20 ft slab, 4 inches thick
- Area: 20 × 20 = 400 square feet.
- Volume: 400 × 4 ÷ 12 = 133.33 cubic feet.
- Cubic yards: 133.33 ÷ 27 = 4.94 cubic yards.
- With 10% waste: 4.94 × 1.10 = 5.43 cubic yards.
- Rounded up to a quarter yard: 5.5 cubic yards.
These are the numbers the calculator shows when the page opens.
Cubic yard conversions
| From | To | Multiply by |
|---|---|---|
| Cubic feet | Cubic yards | 0.037 (divide by 27) |
| Cubic yards | Cubic feet | 27 |
| Cubic metres | Cubic yards | 1.308 |
| Cubic yards | Cubic metres | 0.7646 |
How many square feet a yard of concrete covers
One cubic yard is 27 cubic feet. Divide 27 by the thickness in feet to get the area it covers.
| Thickness | Area covered by 1 cubic yard |
|---|---|
| 3 inches | 108 sq ft |
| 4 inches | 81 sq ft |
| 5 inches | 64.8 sq ft |
| 6 inches | 54 sq ft |
| 8 inches | 40.5 sq ft |
Why the order is rounded up
The calculator shows the exact amount and the same amount rounded up to the next quarter yard. Rounding up is a habit for ordering, because running short in the middle of a pour is the costlier mistake. Suppliers set their own smallest order and their own steps, so ask yours how they round.
What the calculator includes
- This page handles a flat pour with one thickness, or a volume you already know. For footings, walls, columns, steps and curbs, use the shapes on the home page calculator.
- Each dimension can be up to 10,000 in its unit, and an area or volume up to 1,000,000. Waste can be 0 to 50%.
- With square feet or a volume, the preview is a symbol, because the calculator does not know the outline of the pour.
Is it private?
Yes. The calculation and the PDF are made in your browser. The numbers you type are not sent to our server and are not saved.
Tips for an accurate estimate
- Convert every dimension to the same unit before you multiply, or enter each one with its own unit here.
- Round the order up to the increment your supplier sells, never down.
- Ask the plant about its minimum load and any short-load fee before you fix the pour size.
- Add the waste allowance before you round, not after.
- Have the forms, tools and crew ready before the truck arrives, because ready-mix does not wait.
Related calculators
Frequently asked questions
- How many yards of concrete do I need?
- Multiply the length, width and thickness in feet, then divide by 27. A 20 ft by 20 ft slab that is 4 inches thick needs 4.94 cubic yards, or 5.43 cubic yards with 10% waste.
- How many cubic feet are in a yard of concrete?
- 27 cubic feet. A cubic yard is 3 feet by 3 feet by 3 feet.
- How many square feet does a yard of concrete cover?
- It depends on the thickness. One cubic yard covers 81 square feet at 4 inches thick, 54 square feet at 6 inches and 108 square feet at 3 inches.
- How do I convert cubic feet to cubic yards?
- Divide the cubic feet by 27. For example, 100 cubic feet is 3.7 cubic yards. Choose convert a volume in the calculator to do it for you.
- How do I calculate concrete yards from square feet?
- Multiply the square feet by the thickness in inches and divide by 324. For 400 square feet at 4 inches, that is 400 × 4 ÷ 324 = 4.94 cubic yards.
- Is a yard of concrete the same as a cubic yard?
- Yes. When people order concrete, a yard means a cubic yard, which is a volume of 27 cubic feet. It is not a length of 3 feet.
Sources
Every figure this calculator uses comes from the published sources below. The formulas are on this page, so any result can be checked by hand.
- Quikrete, Concrete Mix No. 1101: data sheet and product page. Bag yields: 0.30 ft³ (40 lb), 0.375 ft³ (50 lb), 0.45 ft³ (60 lb) and 0.60 ft³ (80 lb); bags per pallet: 80, 56 and 42.
- Federal Highway Administration (FHWA), Report FHWA-HRT-05-057. Normal-weight concrete: 145 lb per cubic foot (1.96 tons per cubic yard).