How much gravel do you need for a 20×40 area?

A 20×40 ft area (800 sq ft) filled 4 inches deep needs 10.86 cubic yards of gravel including 10% for compaction — about 15.2 tons of pea gravel or 16.3 tons of crusher run.

Change the numbers

The calculator below is pre-filled for this project. Adjust any value — including feet and inches — and the results update instantly.

Weights are typical averages; moisture and stone type change them. Your supplier can confirm their tons-per-yard figure.

Your results

Gravel needed15.21 tons

Volume10.86 cu yd

Weight30,420 lb

0.5 cu ft bags (≈50 lb)587

How much gravel do you need for a 20×40 area — diagram

Gravel for 20×40 ft at different depths

Includes 10% extra for compaction.

Depth	Cubic yards	Tons (pea gravel)	Tons (crusher run)
2 in	5.43	7.6	8.15
3 in	8.15	11.41	12.22
4 in	10.86	15.21	16.3
6 in	16.3	22.81	24.44

What to use for this size

A 20×40 area is driveway-sized. For a driveway, a common build is 4 inches of compacted crusher run topped with 2–3 inches of #57 stone, over landscape fabric on soft soil.

The math

20 × 40 × (4 ÷ 12) = 266.7 cu ft × 1.10 extra = 293.3 cu ft = 10.86 cu yd × 1.4 tons/yd³ = 15.21 tons

Common questions

How many tons of gravel for a 20x40 area?

About 15.2 tons at 4 inches deep (pea gravel, 10% extra included). At 6 inches it's 22.8 tons.

How many yards of gravel for 20x40?

10.86 cubic yards at 4 inches deep, including 10% for compaction.

Want the full method, tips and other sizes? See the gravel calculator guide.

Last reviewed November 1, 2026. Results are estimates — confirm with your supplier.

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