How many cubic yards of gravel do I need?

Last reviewed 1 July 2026

Short answer

Multiply the area in square feet by the depth in feet, then divide by 27. A 300 ft² patio at 3 in deep is 300 × 0.25 = 75 ft³, which is 2.78 cubic yards — call it 3. At about 1.35 tons per cubic yard, that is roughly 3.75 tons.

Work it out for your project with the gravel calculator

The conversions you need

cubic yards = (area in ft² × depth in inches) ÷ 324

Depth in inches expressed as feet
InchesFeetCoverage of 1 yd³
1 in0.0833 ft324 ft²
2 in0.1667 ft162 ft²
3 in0.25 ft108 ft²
4 in0.3333 ft81 ft²
6 in0.5 ft54 ft²
8 in0.6667 ft40.5 ft²

One cubic yard is 27 cubic feet. Coverage = 324 ÷ depth in inches.

Worked examples

Common US gravel jobs
JobAreaDepthCubic yardsApprox. tons
Garden path120 ft²2 in0.741.0
Patio base300 ft²4 in3.705.0
Single driveway surface600 ft²3 in5.567.5
Driveway base600 ft²6 in11.115.0

Tons calculated at about 1.35 tons per cubic yard for gravel. Dense graded base is heavier, around 1.75 tons per cubic yard.

Cubic yards or tons?

US suppliers quote both, and they are not interchangeable without knowing the material. A cubic yard of gravel is about 1.35 tons; a cubic yard of dense graded base is closer to 1.75 tons; a cubic yard of topsoil is around 1.1 tons.

Buying by volume is safer when you need to fill a known space, because you know exactly how much ground it will cover. Buying by weight is what the quarry prefers because it is what the weighbridge measures.

If a supplier quotes tons and you have calculated cubic yards, ask what conversion they use. Do not assume.

Rounding and delivery

  • Most bulk suppliers deliver in half-yard increments with a one-yard minimum.
  • Round up. Coming back for a partial second load costs a full delivery charge.
  • A standard single-axle dump truck carries about 5 cubic yards; a tandem carries 10–14. Splitting an order across two loads doubles the delivery cost.
  • Add 5–10% on top of the calculated figure for spreading losses and depth creep.