Gravel Calculator
ft
ft
in
Cubic Yards1.23
Tons1.73
This gravel calculator estimates how much aggregate you need to cover an area to a chosen depth, reporting both the volume in cubic yards and the approximate weight in tons. It multiplies the length, width, and depth to find the cubic feet, converts that to cubic yards, and applies a typical density of 1.4 tons per cubic yard. Use it to order gravel for a driveway, pathway, drainage bed, or landscaping project.
Formula
Cubic yards = (Length × Width × Depth ÷ 12) ÷ 27; Tons = Cubic yards × 1.4
- Length
- Area length in feet
- Width
- Area width in feet
- Depth
- Gravel depth in inches (divided by 12 to convert to feet)
- 1.4
- Assumed gravel density in tons per cubic yard
How it works
- Enter the length and width of the area in feet and the depth of gravel you want in inches.
- The calculator computes cubic feet as length × width × (depth ÷ 12), then divides by 27 to get cubic yards.
- It multiplies the cubic yards by 1.4 tons per cubic yard to estimate the weight you need to order.
Worked example
A driveway 20 ft long and 10 ft wide covered with gravel 4 inches deep.
- Cubic feet: 20 × 10 × (4 ÷ 12) = 200 × 0.3333 = 66.67 cu ft.
- Cubic yards: 66.67 ÷ 27 = 2.47 cu yd.
- Tons: 2.47 × 1.4 = 3.46 tons.
You need about 2.47 cubic yards, weighing roughly 3.46 tons.
Frequently asked questions
- What gravel density does the calculator assume?
- It uses 1.4 tons per cubic yard, a typical value for common crushed stone and pea gravel. Heavier dense-grade aggregates can run higher, so check your supplier's density if you need an exact tonnage.
- How deep should a gravel driveway be?
- A residential gravel driveway is commonly 4 to 6 inches deep, often built up in layers. Walkways and decorative beds can use 2 to 3 inches, while high-traffic or soft-ground areas may need more.
- Should I order a little extra?
- Yes. Gravel compacts and settles, and edges are rarely perfectly square, so ordering about 5 to 10 percent more than the calculated amount helps you avoid a second delivery.
- Does this work for irregularly shaped areas?
- It assumes a rectangle. For an irregular area, break it into rectangular sections, calculate each one separately, and add the results together for the total volume and weight.