Gravel Calculator

How to Calculate How Much Gravel You Need

This calculator finds the volume of gravel needed to cover a rectangular area to a given depth, using Volume = Length × Width × Depth. It also estimates the total weight using a gravel density you can adjust — a typical loose gravel density is around 100-105 lb per cubic foot (roughly 1,600-1,700 kg per cubic meter), though the exact figure varies by gravel type and grading.

Example

A 10 ft × 10 ft driveway area filled to a 3-inch depth needs 10 × 10 × (3 ÷ 12) = 25 cubic feet of gravel, which is about 0.93 cubic yards and weighs roughly 2,625 lb at a density of 105 lb/ft³. In metric units, a 3 m × 3 m path filled to 8 cm deep needs 3 × 3 × 0.08 = 0.72 cubic meters, weighing about 1,211 kg at a density of 1,682 kg/m³.

Common Use Cases

FAQs

Does gravel density vary by type?

Yes — crushed stone, pea gravel, and river rock all pack and weigh differently depending on particle size, shape, and moisture content, typically somewhere in the 95-115 lb/ft³ (1,500-1,800 kg/m³) range. Adjust the density field above if your supplier gives you a specific figure for your gravel type.

Should I buy extra gravel?

It's common practice to add 5-10% extra to account for compaction, uneven ground, and spillage during handling, especially for larger driveway or path projects.

How do I convert cubic feet to bags of gravel?

Bag sizes vary by brand, but a common 0.5 cubic foot bag is a widely sold size. Divide your total cubic feet by the coverage per bag listed on your chosen product to estimate how many bags to buy.