Figuring out how much topsoil or gravel you need is a tricky business. Below I’ll take you through how our material calculator works and how much various trucks can carry. Be sure to check out our new video for step-by-step instructions on calculating how many cubic yards of material you need.

To visualize how many cubic yards or tons a pickup truck or dump truck can carry, check out our post, “What Does a Cubic Yard Look Like?”

## How do I determine how much material I need?

Calculating how much gravel, sand, or topsoil you need can feel intimidating. Our new video has step-by-step instructions and examples about how to calculate the volume of your project area so that you can determine how many cubic yards of material you need. It also explains why most supply yards sell by the cubic yard rather than by the ton. Check it out below.

You can also find our step-by-step instructions below, followed by a real-life example.

**Step 1: Understand the Volume Equation**

The best way to determine how much material you need is to figure out the volume of the area you need to fill. The volume is the total amount of space inside an object. Below is the formula for measuring volume.

Volume = Length x Width x Depth

This is the formula that our material calculator uses. Our calculator then converts the volume from cubic feet to cubic yards (27 cubic feet = 1 cubic yard).

By the way, if you’re confused about why volume is calculated this way, think of it this way: the volume formula determines the dimensions of a 3D cube. We use abbreviations like yd^{3 }and ft^{3} to represent the three-dimensional volume of a space in yards or feet.

**Step 2: Measure the Length, Width, and Depth of Your Project Area**

Use a measuring tape to measure the length, width, and depth of your project area in feet. Since your depth will likely be in inches, you will need to convert the depth in inches to feet. For example, 3 inches = 0.25 feet.

All of your measurements should use the same unit of measurement (e.g., feet). Otherwise the calculation won’t work.

**Step 3: Multiply the Length x Width x Depth**

Multiply all three measurements together. If your measurements are all in feet, your total will represent how many cubic feet of material you need.

**Step 4: Convert the Total to Cubic Yards, If Needed**

If your total is in cubic feet, you will need to convert to cubic yards. There are 27 cubic feet in 1 cubic yard, so you will divide your total by 27.

## You can learn from this real-life example:

A homeowner had a French drain that’s 95 feet long and 1 foot wide. It needed to be topped off with 2 inches of drain rock.

**First, we needed to estimate the volume of material in cubic yards using the volume formula:**

Volume = Length (95 feet) x Width (1 foot) x Depth (2 inches, which is 0.17 feet)

In other words, Volume = 95 ft x 1 ft x 0.17 ft

After multiplying the numbers, our Volume = 16.2 cubic feet (or 16.2 ft^{3})

Don’t forget to use the same unit of measurement, like feet or inches, for each measurement. That’s why we converted the depth from 2 inches to 0.17 feet. Forgetting to do this is when mistakes most often happen.

**After getting the volume, we converted cubic feet to cubic yards by dividing our total by 27.**

Volume in Cubic Yards = 16.2 ft^{3} ÷ 27 = 0.6 cubic yards (or 0.6 yd^{3)}

**Washington Rock will convert the volume to tonnage for you.**

But just to show you what this looks like, this is the formula we used based on the product and season:

Approximate Tonnage = Cubic Yards x 1.4

In other words, Approximate Tonnage = 0.6 yd^{3 }x 1.4

Our total came out to 0.8 tons.

We ended up using less than 1 ton of material on this project, so our calculations were right on.

## Other Popular Questions

Read the answers to these other popular questions by clicking the link below:

- How many cubic yards of material can my pickup truck or delivery truck carry?
- Why are some materials sold by cubic yards and some sold by tons?

*This post was originally published as a part of “What Does a Cubic Yard Look Like?” on September 27, 2021. For more information about Washington Rock’s rock products, visit our Products page.*