Gravel Calculator
Accurately estimate the volume and weight of gravel required for your driveway, walkway, patio, or landscaping project.
How to Calculate Gravel
Calculating the exact amount of gravel needed for your project is crucial to avoid over-ordering or running short mid-job. To manually calculate the required volume, you must first measure the length and width of the coverage area in feet, and the desired depth in inches. Convert the depth from inches to feet by dividing by 12. Next, multiply the length, width, and converted depth together to find the total volume in cubic feet.
Since most commercial quarries and landscape supply yards sell bulk gravel by the cubic yard, you must convert your cubic feet measurement. Divide your total cubic feet by 27 (since there are 27 cubic feet in a cubic yard). Finally, to convert cubic yards to tons—the standard unit of weight for commercial deliveries—multiply the cubic yards by the density factor of your chosen material. Standard crushed stone typically weighs about 1.4 to 1.45 tons per cubic yard.
What Affects Gravel Coverage & Weight
Several real-world variables can alter the actual amount of gravel you need compared to a raw mathematical calculation. The most significant factor is compaction. When gravel is spread, graded, and compacted using heavy machinery or a plate compactor, the air voids between the stones are reduced. This causes the material to settle, reducing its overall volume by 10% to 15%. To compensate for this compaction loss, professional contractors always add a 10% to 15% safety buffer to their final order.
Additionally, the size and shape of the aggregate dramatically affect the weight-to-volume ratio. Clean, rounded river rocks have more uniform spaces between them, making them lighter per cubic yard than dense, angular crushed stone mixed with fine dust (often called crusher run or road base). Moisture content also plays a role; wet gravel stored outdoors will weigh significantly more than dry gravel, which can affect delivery weight limits and payload capacities.