River Rock Calculator
Calculate cubic yards of river rock for landscaping, drainage, and decorative beds
Enter Dimensions
Enter your dimensions above to see results
Tips & Notes
- •3"–4" depth is standard for decorative landscape beds.
- •Use 6" or more for drainage channels and dry creek beds.
- •River rock has a higher void ratio than crushed stone — order 10–15% extra.
- •Larger stones (3"–5") need more volume to cover the same area than smaller pea gravel.
- •Landscape fabric under river rock prevents weeds and keeps stones from sinking into soil.
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Materials & Supplies
Tools You'll Need
Pro tips for river rock
- ›3"–4" depth is standard for decorative landscape beds.
- ›Use 6" or more for drainage channels and dry creek beds.
- ›River rock has a higher void ratio than crushed stone — order 10–15% extra.
- ›Larger stones (3"–5") need more volume to cover the same area than smaller pea gravel.
- ›Landscape fabric under river rock prevents weeds and keeps stones from sinking into soil.
Frequently asked questions
How many cubic yards of river rock do I need for a 100 sq ft bed?▾
At 3" depth, 100 sq ft needs about 0.93 cubic yards (1 cu yd covers ~108 sq ft at 3"). Order 1.1 cubic yards to allow 10% extra — large river rock has voids that take up more volume than crushed stone.
What's the difference between river rock sizes?▾
Pea-size river rock (1/4"–3/8") works for paths and ground cover. 1"–2" is the most common decorative size. 2"–5" is used for accents, drainage channels, and dry creek beds. Larger sizes need more depth to cover the same area.
Do I need landscape fabric under river rock?▾
Yes — landscape fabric prevents weeds from growing up through the stones and keeps the rock from sinking into the soil over time. Use a heavy-duty woven fabric (not the flimsy spun-bond type) for long-term landscape beds.
How heavy is river rock?▾
River rock weighs roughly 2,700–2,900 lbs per cubic yard (about 100–110 lbs per cubic foot). A standard pickup bed holds about 1 cubic yard but most half-ton trucks can only safely haul 1/2 yard of stone.
How much does river rock cost in 2026?▾
Decorative river rock runs $55–$120/cubic yard delivered, or $5–$10 per 50 lb bag at retail. Larger and rarer colors (Mexican beach pebbles, Montana rainbow) cost $200+/cubic yard.