Gravel Calculator

Using this gravel calculator takes three numbers: the length, width, and depth of the space you want to cover. Enter length and width in feet and depth in inches, then read your result in tons and cubic yards. That's all most people need. If you want more control, open More options to switch to metric, pick a different gravel type (pea gravel, crushed stone, sand, or riprap), enter your square footage directly, add a bag size to see how many bags to buy, or add a price to estimate cost. A common question is *"how much gravel do I need for a 10x20 area?"* — enter 20, 10, and your depth and you'll have the answer in seconds.

Gravel is sold two ways: by volume (cubic yards) if it's delivered loose, and by weight (tons) if you're loading a truck or ordering from a quarry. This calculator gives you both so you can order confidently either way. The trick is depth. Landscapers usually spread decorative gravel like pea gravel about 2 inches deep, driveways 3-4 inches, and a base layer under pavers 4-6 inches. Deeper is not always better — too deep and loose gravel becomes hard to walk or drive on. Because a cubic yard of gravel weighs roughly 1.4 tons, small changes in depth make a real difference in how much you buy, which is exactly why measuring first beats guessing at the store.

The math is a straightforward volume-times-density calculation:

1. Area = length x width (square feet)
2. Volume = area x (depth in inches ÷ 12), giving cubic feet
3. Cubic yards = cubic feet ÷ 27
4. Weight (tons) = cubic feet x density ÷ 2000

Regular gravel weighs about 105 lbs per cubic foot (roughly 2,835 lbs, or 1.42 tons, per cubic yard). Pea gravel is a touch lighter at about 100 lbs/ft³. The calculator swaps in the right density automatically when you pick a gravel type.

Example 1 — a 10x20 pea gravel patio, 2 inches deep: Area = 200 sq ft. Volume = 200 × (2÷12) = 33.3 cubic feet = 1.23 cubic yards. At 100 lbs/ft³ that's about 1.67 tons.

Example 2 — a 40x12 gravel driveway, 4 inches deep: Area = 480 sq ft. Volume = 480 × (4÷12) = 160 cubic feet = 5.93 cubic yards, or about 8.4 tons of regular gravel.

Example 3 — how much gravel by the bag: A 50 lb bag of gravel covers only about 0.5 cubic feet, so that 10x20 patio above (33.3 cu ft) would need roughly 67 bags — which is why bulk delivery is far cheaper for anything larger than a small bed.

- Order about 10% extra — gravel settles and compacts, and edges are never perfectly square.
- Bulk beats bags for anything over about 1 cubic yard; bagged gravel can cost several times more per ton.
- Check delivery minimums — many yards deliver a full 1-yard scoop minimum.
- Lay landscape fabric first under decorative gravel to stop weeds and keep the stone from sinking into soil.
- For driveways, order tons; for garden beds, order cubic yards — match the unit your supplier quotes so nothing gets lost in conversion.