Gravel Calculator
Planning a gravel driveway or landscaping project? Enter your area dimensions and depth to find out how many cubic yards and tons of gravel you need.
How to Calculate Gravel for a Driveway
Gravel volume follows the same formula as any bulk material: length times width times depth. Measure length and width in feet, and depth in inches. Divide depth by 12 to convert to feet, then multiply all three dimensions.
The result is cubic feet. Divide by 27 to get cubic yards. Suppliers price gravel by the ton, so multiply cubic yards by 1.4 to estimate tonnage. Crushed stone is denser than pea gravel, so the multiplier ranges from 1.3 to 1.5 depending on the material.
Always add 5 to 10 percent extra for settling and compaction. Gravel compresses under traffic, and the final depth ends up less than the loose fill. Order enough to compensate.
Choosing the Right Gravel Depth
Depth depends on the application. Decorative pathways need only 2 to 3 inches of gravel over landscape fabric. That is enough to prevent weeds while maintaining a walkable surface.
Driveways handling cars require 4 to 6 inches total. Start with 3 to 4 inches of crushed stone base for stability, then top with 2 inches of surface gravel. The base locks together and resists rutting.
Heavy vehicles or soft soil call for 6 to 8 inches of gravel. Trucks and equipment create deep ruts in thin gravel, especially during wet weather. Extra depth spreads the load and prevents mud from mixing with the surface.
Types of Gravel and Their Uses
Crushed stone is the workhorse for driveways and parking areas. Sharp edges interlock when compacted, creating a firm surface that resists shifting. Sizes range from 3/4 inch down to dust.
Pea gravel is smooth and rounded, ideal for walkways and decorative beds. It does not compact well, so avoid using it for driveways. It is comfortable underfoot and works great in play areas and patios.
River rock is larger and rounder, used mainly for drainage and landscaping accents. It comes in 1 to 3-inch sizes and is too coarse for driveways. Use it around downspouts, in dry creek beds, or as a decorative mulch.
Frequently Asked Questions
How deep should gravel be for a driveway?
Standard driveways need 4 to 6 inches of gravel. Use 4 inches for light vehicles and well-drained soil. Heavy trucks or soft ground require 6 to 8 inches.
How much does a ton of gravel cover?
One ton of gravel covers about 100 square feet at 2 inches deep, 70 square feet at 3 inches, or 50 square feet at 4 inches.
What is the difference between gravel and crushed stone?
Gravel is naturally rounded from water erosion. Crushed stone is mechanically broken rock with sharp edges that compact better for driveways and bases.
How much does gravel cost per ton?
Prices range from $30 to $60 per ton depending on type and location. Delivery adds $50 to $150 depending on distance and load size.
Do I need a base layer under gravel?
Yes, for driveways and high-traffic areas. Lay landscape fabric, then 3 to 4 inches of crushed stone base, topped with 2 to 3 inches of surface gravel.