About this tool
This gravel calculator tells you how much stone to order for a driveway, walkway, patio base, drainage trench, or decorative bed: the loose cubic yards a supplier will load and the tons the load will weigh for the material you choose, from pea gravel and #57 stone to crusher run, sand, river rock, decomposed granite, crushed limestone, and asphalt millings. Enter the area as a rectangle, circle, or a known figure, set the depth, and switch on the compaction allowance when the depth you entered is the finished, rolled thickness. A waste factor covers spillage and uneven subgrade, a bag size gives the count for small jobs, and prices per ton or per cubic yard produce a material cost estimate. It is built for homeowners ordering their first load, and for landscapers who want a fast check on a quote; a metric mode works in meters, centimeters, cubic meters, and tonnes.
How it works
Volume in cubic feet = area in square feet x depth in inches / 12. If the depth is the compacted thickness, the loose volume to order is multiplied by 1 + compaction% (15% is typical for crushed stone), and then by 1 + waste%. Cubic yards = cubic feet / 27, rounded up to the next half yard for ordering. Weight = cubic feet x the material's loose bulk density in pounds per cubic foot, and tons = weight / 2,000. The default densities are typical loose values: pea gravel 96 lb/ft³, #57 stone 100, crusher run and road base 105, sand 100, river rock 90, decomposed granite 95, crushed limestone 95, and asphalt millings 45; all are editable, since moisture and grading change them by 10% or more. Tons per cubic yard = density x 27 / 2,000, so 100 lb/ft³ stone runs 1.35 tons per yard. Metric mode converts to cubic meters (1 yd³ = 0.7646 m³) and tonnes (1 US ton = 0.9072 t).
Frequently asked questions
How many tons of gravel do I need for a driveway?
Multiply length by width in feet, then by the depth in inches, and divide by 12 to get cubic feet; divide by 27 for cubic yards, and multiply by about 1.4 tons per yard for crushed stone. A 10 x 40 ft driveway at 4 inches is 133 cubic feet, 4.9 cubic yards, or roughly 6.9 tons of #57 stone. Most driveways use two layers: 4 inches of crusher run base compacted, then 2 to 3 inches of #57 or pea gravel on top, so run the calculator once for each layer.
How deep should gravel be?
Walkways and decorative beds need 2 to 3 inches over landscape fabric. A driveway for cars needs a 4-inch compacted base plus a 2- to 3-inch surface layer; for trucks or RVs increase the base to 6 to 8 inches. A patio or shed base is usually 4 inches of compacted crusher run, and a French drain is 12 inches or more of washed stone around the pipe. Thinner than 2 inches lets the subgrade show through; thicker surface layers of round gravel just shift underfoot.
What is the difference between a cubic yard and a ton of gravel?
A cubic yard is a volume (27 cubic feet, about a 3 x 3 x 3 ft cube); a ton is a weight (2,000 lb). Suppliers sell either way, and the conversion depends on the material: one cubic yard of dry crushed stone weighs about 2,700 lb (1.35 tons), pea gravel about 2,600 lb, river rock about 2,400 lb, and sand about 2,700 lb, more when wet. The calculator reports both so you can compare quotes given in different units.
Do I need to allow for compaction?
Yes if you will roll or tamp the stone, which you should for any base layer. Crushed stone with fines (crusher run, road base, dense grade) loses 10 to 20 percent of its loose volume when compacted, so a 4-inch finished base needs about 4.6 inches of loose material. Washed, single-size stone such as #57 or pea gravel barely compacts, so leave the toggle off or use 5 percent. Waste is separate: 5 to 10 percent covers spillage, ruts in the subgrade, and the pile the loader leaves behind.