ReckonBoxGravel is bought by weight, not volume
The gravel you need is the area times the depth in feet, divided by 27 for cubic yards, then multiplied by the density for tons. A 200 square foot driveway at 4 inches is 2.47 cubic yards, and at 1.4 tons per cubic yard, about 3.46 tons.
That last step trips people up. You measure a driveway in feet and think in cubic yards, but the supplier sells and bills by the ton. So the volume you calculate has to become weight before you can order, and the bridge between them is density. Skip it and you are asking for 2.47 of a unit the quarry does not sell.
Density is a range, so it is an input
Gravel weighs 1.4 to 1.7 tons per cubic yard, depending on the stone size and how wet it is. A generic calculator that hides a single density figure is guessing for you.
Pea gravel packs lighter, crushed stone with fines heavier, and a rained-on pile weighs more than a dry one. That is a spread of more than 20 percent, enough to change a 3-ton order into a 3.6-ton one. This tool takes density as a number you can set, so a figure from your own supplier beats the national average every time. When in doubt, 1.4 is the conservative low end.
Coverage falls fast with depth
One ton of gravel covers about 120 square feet at 2 inches deep, and only about 60 square feet at a 4 inch driveway depth. Double the depth and you halve the coverage, so a deep base layer burns through tonnage far quicker than a decorative topping.
| Depth | One ton covers |
|---|---|
| 2 inches | about 120 sq ft |
| 4 inches | about 60 sq ft |
A gravel driveway usually runs about 4 inches of surface stone, often over a deeper compacted base of larger rock. Paths and decorative beds sit at 2 to 3 inches. Because depth drives volume directly, moving from 3 to 4 inches adds a third more gravel and a third more cost.
The overage a flat waste factor misses
Most material calculators add a flat 10 percent for spillage, which is right for loose gravel you rake into place. Gravel destined for a driveway base is different: it gets compacted, and compaction squeezes the loose volume down, so the tonnage you spread is less than the tonnage that ends up in the finished layer. For a compacted job the overage climbs toward 30 percent. This tool lets you set that number, and it names compaction when you do, so the driveway does not come up thin after the plate compactor passes.
What this does not cover
This estimates a rectangular area of even depth in cubic yards and tons. It does not size the separate, coarser base course under a driveway, which is its own calculation at its own depth, and it does not account for a crowned or sloped surface that holds more in the middle. Delivery is usually priced per ton plus a haul fee that depends on distance, which the material figure alone cannot capture. The tonnage is the order, not the full driveway spec.
Ask the supplier for their density before you order, because a number off a website can be a half-ton wrong on a driveway.
Frequently asked questions
How much gravel do I need? Multiply the area by the depth in feet, divide by 27 for cubic yards, then multiply by the density for tons. A 200 square foot driveway at 4 inches is 2.47 cubic yards, and at 1.4 tons per cubic yard that is 3.46 tons. Bulk gravel is sold by weight, so the tonnage is the number the supplier bills.
How do I convert cubic yards of gravel to tons? Multiply cubic yards by the density in tons per cubic yard. Gravel typically weighs 1.4 to 1.7 tons per cubic yard, so 2.47 cubic yards is about 3.46 tons at the low end. The exact density depends on the stone size and moisture, so a supplier figure beats a generic one, which is why this tool takes density as an input.
How much area does a ton of gravel cover? One ton of gravel covers roughly 120 square feet at 2 inches deep and about 60 square feet at a 4 inch driveway depth. That comes from a ton being around 0.7 cubic yards, spread over the area the depth allows. Doubling the depth halves the coverage, which is why a deep base layer eats gravel far faster than a thin topping.
How much extra gravel should I order? Order about 10% extra for spillage and an uneven surface, and up to 30% more for gravel that will be compacted, since compaction reduces the loose volume you spread. A driveway base tamped down settles noticeably, so the loose tonnage you buy is more than the finished layer suggests. This tool lets you set the overage to match.
How deep should a gravel driveway be? A gravel driveway is usually about 4 inches of surface gravel, often over a deeper compacted base of larger stone. Paths and decorative areas run 2 to 3 inches. Depth drives the volume directly, so going from 3 to 4 inches adds a third more gravel. This tool takes depth in inches and converts it for the cubic yards and tons.