Aggregate, Gravel and Sand Calculator: Volume and Tonnage
This calculator estimates the gravel, sand, or aggregate you need in both cubic yards and tons for sub-base, backfill, and bedding. Enter your area and depth to size a driveway base, slab sub-base, or drainage layer.
Estimated concrete
Estimates only. Add ~5–10% for waste. Bag yields: 40 lb ≈ 0.30, 60 lb ≈ 0.45, 80 lb ≈ 0.60 cu ft. Concrete ≈ 150 lb per cu ft.
How to Use the Aggregate, Gravel and Sand Calculator
- 1
Enter your dimensions
Type the length, width and thickness of your slab, footing or pad and choose your units, feet, inches or meters.
- 2
Get instant volume
See the result in cubic yards, cubic feet and cubic meters, plus weight, the moment you type, no page reloads.
- 3
Buy the right amount
We convert volume into the exact number of 40, 60 and 80 lb bags, truck loads and cost so you order without waste or shortfalls.
The formula
tons = (Area_ft² × (Depth_in ÷ 12) ÷ 27) × 1.4
- ·Area_ft² = coverage area = length × width (ft²)
- ·Depth_in = compacted layer depth (inches)
- ·÷ 12 = converts inches of depth to feet
- ·÷ 27 = converts cubic feet to cubic yards
- ·1.4 = approximate tons per cubic yard of gravel/sand
Aggregate depth is entered in inches, so it is divided by 12 to get feet before multiplying by the area. The 1.4 factor is a working average; wet sand or dense crushed stone can run slightly heavier.
Worked examples
Example 1: 4-inch gravel sub-base under a 200 ft² slab
- Cubic feet = 200 × (4 ÷ 12) = 66.67 ft³
- Cubic yards = 66.67 ÷ 27 = 2.47 yd³
- Tons = 2.47 × 1.4 = 3.46 tons
Result: About 2.47 yd³ (~3.46 tons) of gravel
Example 2: 3-inch sand bed for a 10 ft × 12 ft patio
- Area = 10 × 12 = 120 ft²
- Cubic feet = 120 × (3 ÷ 12) = 30 ft³
- Cubic yards = 30 ÷ 27 = 1.11 yd³
- Tons = 1.11 × 1.4 = 1.56 tons
Result: About 1.11 yd³ (~1.56 tons) of sand
Concrete calculators by project type
Concrete bag yield & coverage
How much mixed concrete a standard bag yields, and how far a cubic yard goes at common slab depths.
| Bag size | Yield (cu ft) | Bags per cubic yard |
|---|---|---|
| 40 lb | 0.30 | 90 |
| 60 lb | 0.45 | 60 |
| 80 lb | 0.60 | 45 |
- 40 lb
- 60 lb
- 80 lb
Related guides
Aggregate and Gravel FAQs
How many tons of gravel are in a cubic yard?
Most gravel and crushed stone weighs about 1.4 to 1.5 tons per cubic yard, so one yard is roughly 1.4 tons for estimating purposes.
How deep should a gravel sub-base be under concrete?
A compacted gravel sub-base is typically 4 to 6 inches deep for slabs and patios, and thicker for driveways carrying heavier loads.
How do I calculate how much gravel I need?
Multiply the area in square feet by the depth in feet to get cubic feet, then divide by 27 for cubic yards. Multiply yards by about 1.4 to estimate tons.
How much does a cubic yard of sand weigh?
Dry sand weighs roughly 1.3 to 1.4 tons per cubic yard, and slightly more when damp.
Should I order aggregate by the yard or by the ton?
Suppliers sell both ways. Calculate the volume in cubic yards first, then convert to tons using the material's density so you can compare quotes and order correctly.
How much extra aggregate should I order for compaction?
Add about 10 to 15 percent because loose aggregate compacts down when tamped or rolled into a stable sub-base.
What size gravel is best for a concrete sub-base?
A 3/4-inch crushed stone or a dense-graded road base (crusher run) is the standard choice under concrete. Angular crushed stone locks together and compacts far better than rounded pea gravel, which tends to shift under load. This gives the slab a stable, well-draining foundation.
Can I pour concrete directly on soil without gravel?
You can on well-drained, undisturbed soil, but a 4-inch compacted gravel base is strongly recommended for most slabs. Gravel provides uniform support, improves drainage, and reduces cracking from soil movement and frost heave. Skipping it is a common cause of premature slab failure.
How do I convert cubic yards of aggregate to tons?
Multiply cubic yards by roughly 1.4 to get tons for typical gravel and sand. For example, 3 cubic yards is about 4.2 tons. The exact factor varies with moisture and stone type, so confirm the density with your supplier for large orders.
What is the difference between gravel and crushed stone?
Gravel is naturally rounded stone shaped by water, while crushed stone is mechanically broken and has sharp, angular faces. Crushed stone compacts into a more stable, interlocking base, which is why it is preferred under concrete. Rounded gravel is better suited to drainage layers and decorative uses.
How much does a cubic yard of gravel cost?
Delivered gravel typically runs about $40 to $75 per cubic yard, or roughly $30 to $55 per ton, depending on stone type and your region. Delivery fees and smaller orders push the per-yard price higher. Buying by the full truckload is usually the cheapest way to purchase base material.
Does this calculator include extra for compaction?
No, the base result reflects the finished, compacted depth you enter. Because loose gravel and sand settle when tamped, order about 10 to 20 percent extra to reach your target depth after compaction. Add more if the sub-grade is soft and some material will press into the soil.
How thick should a gravel base be under a driveway slab?
A concrete driveway generally needs 4 to 6 inches of compacted gravel base, and up to 8 inches over soft or clay-heavy soils. The thicker base spreads vehicle loads and resists frost movement. Always compact the gravel in layers rather than dumping it all at once.