What this calculator does
The gravel calculator estimates material for a rectangular area such as a walkway, shed base, drainage area, or landscape bed. It converts your dimensions into square feet, cubic feet, cubic yards, estimated pounds, tons, and optional material cost.
Formula overview
The core volume estimate is length times width times depth after each measurement is converted to feet. Cubic feet are divided by 27 to convert to cubic yards. Weight is then estimated by multiplying cubic yards by the editable density assumption.
Cubic yards and tons
Gravel is often quoted by cubic yard or by ton. Cubic yards describe volume. Tons describe weight. The relationship between them depends on density, so the calculator keeps density visible and editable.
Why density varies
Gravel density changes with stone type, size distribution, moisture, supplier measurement practices, and compaction. The default density is only a planning assumption, not a universal property of gravel.
Worked example
A 20 ft by 12 ft area at 3 inches deep is 240 square feet. A 3 inch depth is 0.25 ft, so the volume is 60 cubic feet, or about 2.22 cubic yards. At 2,835 lb per cubic yard, that is about 6,300 lb before allowance. With a 10% allowance, the estimate is about 3.5 tons to purchase.
Assumptions and limitations
This tool is for material quantity planning. It does not provide structural, engineering, drainage, or code-compliance advice. Confirm final quantities with your supplier, especially when the gravel type, compaction, or project requirements are specific.