Gravel Calculator
Area (sq ft) × depth (in) ÷ 324 = cubic yards, then multiply by the stone's weight: a 10 × 50 ft layer 4 in deep is 6.17 cubic yards, about 8.3–9 tons of crushed stone.
Gravel estimator
How to calculate gravel
cubic yards = length (ft) × width (ft) × depth (in) ÷ 324 tons = cubic yards × tons per cubic yard pounds = tons × 2,000
Worked example: 10 × 50 ft at 4 in = 500 × 4 ÷ 324 = 6.173 cu yd. Quarries often sell by the ton, so multiply by the weight of the stone you are buying.
Gravel weight per cubic yard
Typical values, vary by supplier: ask yours. Loose weights below come from one landscape retailer and the Engineering ToolBox. We could not verify a loose weight for decomposed granite or crushed limestone from a quarry or DOT, so for those the calculator asks for your supplier's number.
| Material | Tons per cu yd | Source |
|---|---|---|
| Pea gravel (3/8 in) | 1.25–1.35 | Mulch Mound (landscape supplier) |
| #57 / crushed drainage stone | 1.35–1.45 | Mulch Mound (landscape supplier) |
| River rock (1–3 in) | 1.4–1.5 | Mulch Mound (landscape supplier) |
| Gravel, dry (general) | 1.42 | The Engineering ToolBox |
| Sand (mason sand) | 1.31–1.35 | Mulch Mound (landscape supplier) |
| Crushed limestone | ask supplier | not verified |
| Decomposed granite | ask supplier | not verified |
| Compacted aggregate base (pay factor) | 1.8 | Illinois DOT |
Gravel sizes: #57, #8 and more
| Size number | Gradation (percent passing) |
|---|---|
| #3 | 100% through 2 1/2 in; 90–100% through 2 in; 35–70% through 1 1/2 in |
| #4 | 100% through 2 in; 90–100% through 1 1/2 in; 20–55% through 1 in |
| #57 | 100% through 1 1/2 in; 95–100% through 1 in; 25–60% through 1/2 in; 0–10% through #4 |
| #8 | 100% through 1/2 in; 85–100% through 3/8 in; 10–30% through #4 |
Gradations from New Enterprise Stone & Lime's AASHTO size chart. A smaller number means bigger stone. #57 (about 1 in down to 0.19 in) is a common driveway and drainage stone; #8 (3/8 in down to 0.094 in) is sometimes sold as 1B or 1/2 in.
Frequently asked questions
How much gravel do I need?
Multiply length × width in feet by depth in inches, divide by 12 for cubic feet and by 27 for cubic yards. A 10 × 50 ft driveway layer 4 inches deep is 6.17 cubic yards. At a typical 1.35 to 1.45 tons per yard for crushed drainage stone, that is about 8.3 to 9 tons.
How many tons is a yard of gravel?
Typical loose figures from one landscape supplier (Mulch Mound): pea gravel 2,500 to 2,700 lb (about 1.25 to 1.35 tons), crushed drainage stone 1.35 to 1.45 tons, 1 to 3 in river rock 1.4 to 1.5 tons. The Engineering ToolBox lists dry gravel at 105 lb per cubic foot, about 1.42 tons per yard. Weights vary with the stone and moisture, so ask your supplier.
What size is #57 stone?
#57 is a blend of #5 and #7 sizes, about 1 inch down to 0.19 inch (Chaney Enterprises). Under the AASHTO/ASTM size number 57 gradation, 100% passes a 1 1/2 in sieve and 95 to 100% passes 1 in. York Building Products notes it is also called PA 2B and is common for stone driveways.
How deep should gravel be?
It depends on the job. The University of Maryland Extension says to apply gravel, stone or lava rock as mulch in a 1-inch layer. Driveways and paths are built in thicker layers; follow your plan or your supplier's advice for base and top layers.
Why does compacted gravel need more tons?
Compaction packs more stone into each yard. The Illinois DOT converts compacted aggregate base course to tons with a factor of 1.8 tons per cubic yard, higher than loose landscape figures.
Sources
- How Many Tons of River Rock Do You Actually Need, Mulch Mound (landscape supplier). Used for: pea gravel 2,500–2,700 lb/yd and river rock 2,800–3,000 lb/yd (typical, supplier figures); pea gravel 3/8 in or less.
- How Much Gravel for a French Drain?, Mulch Mound (landscape supplier). Used for: crushed drainage stone 1.35–1.45 tons/yd (typical, supplier figure).
- Sand Delivery (mason sand FAQ), Mulch Mound (landscape supplier). Used for: mason sand about 1.35 tons/yd (supplier figure).
- Dirt and Mud: Densities, The Engineering ToolBox. Used for: dry gravel 105 lb/cu ft and dry sand 97 lb/cu ft.
- Plan Preparation Memorandum 30-01 (aggregate tonnage factor), Illinois Department of Transportation. Used for: compacted aggregate base factor 1.8 tons/yd.
- Size & Grading Requirements for Coarse Aggregates, New Enterprise Stone & Lime Co.. Used for: AASHTO size number gradations (#57, #8, #4, #3).
- Aggregate Sizing Explained, Chaney Enterprises. Used for: #57 is about 1 to 0.19 in; #8 is 3/8 to 0.094 in.
- Aggregate Products Portfolio, York Building Products. Used for: #57 also called PA 2B, used for stone driveways.
- Mulching Trees and Shrubs, University of Maryland Extension. Used for: stone as mulch in a 1 in layer.
- Quikrete 0.5 Cu. Ft. 50 Lb. All-Purpose Gravel, Do it Best (product listing). Used for: 0.5 cu ft (50 lb) bag of all-purpose gravel.
Estimates only. Check local codes and your product's label. Found a number that does not match its source? Send a correction.