Gravel Calculator: How Much Gravel Do You Need?

If you’re working on a landscaping project and need pea gravel or aggregate, use our gravel calculator to estimate how much to purchase. Enter the length, width, and depth of the area, and our landscape rock calculator will determine the amount of gravel you need in volume and weight.

Gravel Calculator and Formula

If you know the area’s length, width, and depth, enter the information below. Or, enter the desired depth and square footage.

To manually calculate how much gravel you need, measure the length, width, and desired depth of the area in feet, then multiply those numbers to determine cubic feet. Next, divide your cubic feet value by 27 to determine cubic yards. Finally, to convert cubic yards to tons, multiply by 1.4.

Cubic feet = length x width x depth in feet

Cubic yards = cubic feet ÷ 27

Tons = cubic yards x 1.4

Here’s an example:

You want to add pea gravel to a flower bed surrounding your home. The flower bed measures 30 feet long by 4 feet wide, and you’d like your pea gravel to be 3 inches thick, which equates to .25 feet. You multiply those numbers to determine the cubic feet of the area.

30 x 4 x .25 = 30 cubic feet

To convert your cubic feet to cubic yards, divide by 27.

30 ÷ 27 = 1.111 cubic yards

Then, to determine tons, multiply by 1.4.

1.111 x 1.4 = 1.555 tons

You can also use our pea gravel calculator above for much easier calculations.

How Much Gravel Do I Need: Determining Depth

Gravel Calculator

The amount of gravel you need depends on the square footage of the area and the desired gravel depth.

For example, laying a pea gravel pathway requires 3-6 inches of depth, depending on the base soil. For softer base soil, you’ll need 4-6 inches, but if the ground is firm and stable, you may need only 3-4 inches. If you’re using pea gravel instead of mulch to landscape, it should be about 2 – 2.5 inches thick.

Driveways typically require crushed stone, which is different from gravel.

Types of Gravel

Gravel is a naturally occurring material. It’s common for landscaping, while contractors use crushed stone for driveways and construction. Gravel is classified by name or size. When organized by size, it will have a # sign and a corresponding number attached to it. The smaller the number, the larger the gravel.

Here are some of the most common types of gravel:

  • Pea gravel – Pea gravel gets its name from its small size, similar to a pea. It’s inexpensive, with variation in color and shape, making it a go-to for landscaping projects and as an aggregate in construction.
  • River rock – River rock, sometimes called river stone, comes from rivers and creeks. It has a smooth, rounded appearance and comes in many colors, including white, light brown, and black. It comes in many sizes, ranging from small to medium.
  • Lava Rock– Also known as volcanic rock, lava rock comes from cooled lava. Most lava rock is red, black, or gray and is suitable for landscaping projects.
  • Bank gravel – Bank gravel comes from the banks of rivers and creeks. It is a mixture of large rocks, small rocks, and sand, ideal for landscaping projects because of its drainage properties.
  • Marble chips – As the name implies, marble chips come from marble. They are white and standard for landscaping projects, including flower beds and walkways.

Frequently Asked Questions (FAQ)FAQ

Is gravel the same as crushed stone?

Gravel and crushed stone are different. Aggregate companies produce crushed stone by mining for large rocks and crushing them into smaller, angular pieces. Crush is ideal for driveways and construction products, while gravel is better for landscaping.

How many square feet will ten cubic yards of gravel cover?

The area a cubic yard of gravel will cover depends on the depth. A cubic yard of gravel covers about 108 square feet at three inches thick. At 2.5 inches deep, a cubic yard of gravel covers 129.6 square feet.

How many square feet does one ton of gravel cover?

The area that one ton of gravel covers depends on how thick you lay it. One ton of gravel will cover about 76 square feet at three inches thick or 91 square feet at 2.5 inches deep.

How much is a cubic yard of gravel?

The cubic yard is a volume measurement of 3 feet x 3 feet x 3 feet. It’s equivalent to 1.4 tons and covers 108 square feet at three inches thick.