TrowelMath

Gravel for a 12×40 area

  • ENERGY STAR sizing · manufacturer bag yields
  • Updated Oct 23, 2026
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DepthCu ydTons (≈1.4 t/yd³)
2″2.964.15
3″4.446.22
4″5.938.30
6″8.8912.44
8″11.8516.59

Worked example

12 × 40 = 480 sq ft; × 4 in ÷ 12 = 160.0 cu ft; ÷ 27 = 5.93 yd³ ≈ 8.30 tons. Density varies by stone type and moisture, so confirm with your supplier.

Frequently asked questions

How many tons of gravel for 12×40?

About 8.30 tons at 4 inches.