Gravel Calculator: How Much Gravel Do You Need?

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Estimated Gravel Cost:

$39.90 to $44.10

About the Gravel Calculator

This gravel calculator allows you to find out how much gravel you need for your yard, driveway, landscaping path, or other construction project. The calculation is based on the dimensions of the area, including depth, that will be filled in with gravel. For example, you may want to calculate the amount of gravel needed to cover a garden. Gravel gardens are low-maintenance and can be a great drought-tolerant landscaping idea. Gravel can also be used to make paths, such as through your backyard, or it can be used for gravel driveways. Once you know the dimensions of the area that you want to cover, the gravel calculator gives you a certain volume of gravel that you would need. Based on the type of material that you want to use, such as pea gravel, river rock, crushed limestone, or sand, the weight and estimated cost of gravel is also calculated.

How to Use the Gravel Calculator

You can quickly determine “how much gravel do I need” by using a gravel calculator. To use this page to calculate pea gravel and other gravel types, you can follow these calculation steps:

  1. Find the area to be covered with gravel
  2. Area is the space that the gravel will cover. You will need to know the surface area of the project in order to calculate the volume of gravel needed. For rectangular areas, such as driveways or straight paths, you can find the surface area by multiplying the length of the area by the width. Circular areas can be found by the formula πr2, where r is the radius and pi (π) is roughly 3.14.

    Area of Rectangle = Length x Width

    Area of Circle = πr2

    For example, let’s say that you want to build a two-car gravel driveway. The dimensions for this driveway is 24 feet by 20 feet. Using the formula for the area of a rectangle, the area is 480 square feet.

    Area = 24 feet x 20 feet

    Area = 480 ft2

    For more complex and irregular shapes, you can use a square footage calculator to find the area.

  3. Find the volume of gravel needed
  4. Once you know the surface area to be covered, you can easily find the volume of gravel needed by multiplying area by depth. The depth to be used is how deep you want the gravel to be. A common depth is 4 inches for gravel paths. For high-traffic uses with larger loads, you will need a thicker gravel layer. A gravel driveway might have a thickness of 12 inches to 18 inches.

    From our driveway example, let’s say that the gravel will be 12 inches deep, or 1 foot deep, and covers an area of 480 square feet.

    Volume of Gravel = Area x Depth

    Volume of Gravel = 480 square feet x 1 foot

    Volume of Gravel = 480 cubic feet (ft3)

    Volume can also be written in cubic yards, gallons, or liters. You can use a unit converter to convert between units. This gravel calculator also allows you to select your own units.

  5. Find the gravel’s weight
  6. It’s common to price bulk gravel by the ton, which is why knowing the weight is important. Other common quotes for gravel can be by the yard or by the truckload, which is why this page allows you to calculate yards of gravel.

    To find the weight of the gravel, you will need to know the gravel’s density. This is how heavy the gravel is for a certain volume. Different materials will have different densities. For example, the density of gravel is about 105 lbs per cubic feet. Pea gravel has a density of 95 lbs per cubic feet, while crushed limestone can have a density as high as 140 lbs per cubic feet.

    Gravel Weight = Volume (ft3) x Density (lbs/(ft3)

    Let’s say that we want to use pea gravel for our driveway. With a volume of 480 cubic feet, the weight would be about 45,600 lbs. That’s roughly 22.8 tons of pea gravel.

    Pea Gravel Weight = 480 cubic feet x (95 lbs per cubic feet)

    Pea Gravel Weight = 45,600 lbs

  7. Estimate the gravel cost
  8. The cost of gravel can vary depending on your location, the amount of gravel you are buying, and the season. It’s cheaper to buy bulk gravel compared to buying bagged gravel. Since this is a large project, let's say that you are buying bulk pea gravel at $45 per ton. SInce you need 22.8 tons of pea gravel, it would cost about $1,026 for the gravel alone. This doesn’t include delivery and labor.

    Pea Gravel Cost = 22.8 tons x $45 per ton

    Pea Gravel Cost = $1,026

Gravel Depth

The minimum gravel depth required depends on its intended use. For example, you might have a layer of gravel as a base for concrete, with the depth of the gravel being dependent on the thickness of the concrete slab. Calculating concrete weight and dimensions can help you determine how much gravel you will need as a base. For paths, you would need the gravel layer to be thick enough to prevent weeds from growing in it if there will not be a weed barrier.

While gravel can be used as a subbase for drainage and to form a sturdy base, it can also be used as the top layer. This would be the case for gravel gardens, where soil is used as a base, with gravel being placed on top.

Paths may have a gravel depth of 2 inches to 4 inches, while driveways would need gravel to be at least 4 inches thick on top of a base layer. This base layer might be larger gravel or stone pieces.

Common types of gravel include pea gravel, crushed stones, crushed limestone, and river stone. The size of gravel can also vary. For example, crushed stone can be 2 to 4 inches wide, 1 inch wide, or smaller. Stone dust can also be used for paving projects.

Common Densities

Gravel105 lbs/cubic feet (ft3)
Pea Gravel95 lbs/cubic feet (ft3)
River Rock90 lbs/cubic feet (ft3)
Crushed Limestone140 lbs/cubic feet (ft3)
Sand (Wet)120 lbs/cubic feet (ft3)
Sand (Dry)100 lbs/cubic feet (ft3)
Topsoil100 lbs/cubic feet (ft3)
Any calculators or content on this page is provided for general information purposes only. Casaplorer does not guarantee the accuracy of information shown and is not responsible for any consequences of its use.