River Rock Calculator
River rock adds a natural look to garden beds, walkways, and drainage areas. Plug in your project dimensions and depth to find out how many tons to order. River rock is heavier than gravel at roughly 105 lb/ft³, so getting the right estimate saves you from overspending or making extra trips.
How to Estimate River Rock
River rock volume works the same way as any fill material: length x width x depth. The tricky part is converting that volume to weight, since suppliers sell by the ton.
Quick reference for a 10 x 10 ft area:
- 2 inches deep: ~0.37 cubic yards, ~0.49 tons
- 3 inches deep: ~0.56 cubic yards, ~0.73 tons
- 4 inches deep: ~0.74 cubic yards, ~0.97 tons
Choosing the Right Depth
- Garden borders and accents: 2 inches is usually enough to cover the ground and block weeds
- Walkways and paths: 3-4 inches gives a stable walking surface
- Drainage areas and dry creek beds: 4-6 inches for proper water flow
River Rock vs. Gravel
River rock is tumbled smooth by water, so it does not compact like angular crushed stone. That makes it great for decorative use but less ideal for driveways where you need a firm base.