Spike's Calculators

# Concrete from Square Footage

Calculate the amount of concrete you will need from an area measured in square feet.
##### Formula
```Cubic feet = S * D
where S is the area in square feet
D the depth of the area in inches ```
##### Example Calculation
```slab has an area of 425 square feet
the average depth is 4 inches```

`First convert the 4 inches to feet by dividing by 12.`
`4 ÷ 12 = 0.3333`
`4 inches = 0.3333 feet`

`Calculate the volume in cubic feet by multiplying the area by the dept of the slab.`
`425 * 0.3333 = 141.6666  rounded to 142`
`You will need 142 cubic feet of concrete for this slab.`

### Calculator

Square Footage of Area ft²
Slab Thickness in.
Waste:   %

#### Results:

 Concrete Needed in Cubic Feet: ft³ Cubic Yards: yd³ Cubic Metres: m³

#### Calculation

1. enter the square footage of the area
2. the depth of slab in inches
3. waste factor (if required) in a percentage

#### Results

1. amount of concrete needed in cubic feet
2. in cubic yards
3. in cubic metres

### When Ordering Concrete

This concrete calculator will help you in estimating the amount of concrete needed for your project. The amount given as needed, does not include any waste. It is recommended, depending on the job you are doing, to add anywhere from an extra 4% to 10% to your concrete order to make sure you have enough concrete to finish the job. Ask when ordering the concrete. They will be able to give you a good idea of what is needed.