River rock calculator
A 10 ft by 10 ft area covered 2 inches deep needs 0.62 cubic yards of river rock, about 0.82 tons at 2,650 lb per cubic yard. The calculator uses 2,650 lb per cubic yard (Pro Green Services).
0 uses the published 2,650 lb/yd³
Optional; 0 leaves cost out
A 10 ft by 10 ft area covered 2 inches deep needs 0.62 cubic yards of river rock, about 0.82 tons at 2,650 lb per cubic yard.
- Cubic yards
- 0.62
- Cubic feet
- 16.7
- Tons
- 0.82
- Pounds
- 1,636
- Tons at the published range, same condition
- 0.75–0.83
- Rounded up to the next half yard
- 1 yd³
How it is calculated
- Area = 10 ft × 10 ft = 100 sq ft.
- Volume = 100 sq ft × 2 in ÷ 12 = 16.67 cu ft.
- Cubic yards = 16.67 ÷ 27 = 0.617 yd³.
- Weight = 0.617 yd³ × 2,650 lb/yd³ = 1,636 lb; ÷ 2,000 lb per ton = 0.82 tons.
How to calculate river rock in cubic yards and tons
The worked numbers use the calculator's defaults: a 10 ft by 10 ft area 2 inches deep, the calculator's default depth for river rock.
Step 1: area in square feet
Rectangle: length × width
Circle: π × diameter² ÷ 4
Triangle: base × height ÷ 2
Example 10 ft × 10 ft = 100 sq ft
Split an irregular area into rectangles, circles and triangles and add their areas.
Step 2: cubic feet from area and depth
Cubic feet = area in sq ft × depth in inches ÷ 12
Example 100 × 2 ÷ 12 = 16.67 cu ft
Step 3: cubic yards from cubic feet
Cubic yards = cubic feet ÷ 27
Example 16.67 ÷ 27 = 0.617 cubic yards
Step 4: tons from cubic yards
Tons = cubic yards × pounds per cubic yard ÷ 2,000
Example River rock at 2,650 lb per cubic yard (Pro Green Services): 0.617 × 2,650 ÷ 2,000 = 0.82 tons
River rock for common areas
| Area, sq ft | 1 inch deep | 2 inches deep |
|---|---|---|
| 50 | 0.15 yd³ · 0.2 t | 0.31 yd³ · 0.41 t |
| 100 | 0.31 yd³ · 0.41 t | 0.62 yd³ · 0.82 t |
| 200 | 0.62 yd³ · 0.82 t | 1.23 yd³ · 1.64 t |
| 500 | 1.54 yd³ · 2.04 t | 3.09 yd³ · 4.09 t |
| 1,000 | 3.09 yd³ · 4.09 t | 6.17 yd³ · 8.18 t |
How much does a yard of river rock cover?
One cubic yard of river rock covers 162 sq ft at 2 inches deep; one ton at 2,650 lb per cubic yard covers 122 sq ft at the same depth.
| Depth, in | 1 cubic yard covers, sq ft | 1 ton covers, sq ft |
|---|---|---|
| 1 | 324 | 245 |
| 2 | 162 | 122 |
| 3 | 108 | 82 |
| 4 | 81 | 61 |
- 1 cubic yard
- 1 ton
Recommended river rock depth by use
Published depths for river rock run from 1 inch to 2 inches, depending on the use; each row names its document.
| Use | Depth, in | 1 cubic yard covers, sq ft | Source |
|---|---|---|---|
| Garden gravel path (river run, round pieces), practical minimum | 2 | 162 | University of California Agriculture and Natural Resources, Contra Costa Master Gardeners |
| Landscape mulch layer (gravel, pebbles, stones) | 1 | 324 | Mississippi State University Extension |
River rock weight per cubic yard
A cubic yard of river rock weighs about 2,650 lb (1.32 tons) (Pro Green Services). One ton of river rock is about 0.75 cubic yards.
| Pounds per cubic yard | 2,650 |
|---|---|
| Published as | “River Rock (all)”, 1.325 ton/yd³, Pro Green Services; condition: not stated. |
| Published range, same condition, lb | 2,430–2,700 |
| Tons per cubic yard | 1.33 |
| Cubic yards per ton | 0.75 |
Every published value with its source, and tables of weight by volume and yards by tons: River rock weight.
River rock compared with other gravel and stone
| Material | Condition | Pounds per cubic yard | Cubic yards per ton |
|---|---|---|---|
| Crusher run | compacted | 3,770 | 0.53 |
| Pea gravel | not stated | 2,840 | 0.7 |
| Sand | loose | 2,795 | 0.72 |
| River rock | not stated | 2,650 | 0.75 |
| Rock | loose | 2,570 | 0.78 |
| Gravel | loose | 2,565 | 0.78 |
River rock questions
How much river rock do I need?
A 10 ft by 10 ft area covered 2 inches deep needs 0.62 cubic yards of river rock, about 0.82 tons at 2,650 lb per cubic yard. One cubic yard of river rock covers 162 sq ft at 2 inches deep, so divide the area in square feet by 162 for the cubic yards at that depth.
Why the river rock you need can differ from the result
The weight of river rock changes with the source, the moisture and how tightly it is packed, so published values differ (here from 2,430 to 2,700 lb per cubic yard across all conditions). Before ordering, ask the supplier for the weight per yard of their own material and enter it as your own density under More options.
No document gives a compacted weight or a compaction factor for river rock: a compacted layer takes more than the tons shown, so ask the supplier.