Aggregate Calculator
Estimate how much aggregate you need for a sub-base, driveway, or hardcore layer — in cubic yards, tons, and bags, with the density and formula shown.
You need · incl. +10% extra
- Cubic feet
- 36.67 ft³
- Cubic meters
- 1.04 m³
- Pounds
- 3,802 lb
- Kilograms
- 1,725 kg
- Area
- 100 ft²
- Exact volume
- 1.23 yd³
- Density
- 1.4 t/yd³
- Bag size
- 0.5 ft³ bag
Order about 10% extra for compaction and spillage; 15% over soft or uneven ground where the layer settles into the subgrade.
Sub-base for a driveway or patio: 4–6 in compacted. Footpaths and light areas: 2–3 in. Heavy/vehicular areas: up to 8 in.
The formula & constants
Volume = Area × Depth. Convert to cubic yards (1 yd³ = 27 ft³), then Tons = Cubic yards × Density (aggregate ≈ 1.4 tons/yd³).
| Aggregate density (working value) | 1.4 tons/yd³ |
| Typical range | 1.3–1.7 tons/yd³ |
| Cubic-yard conversion | 1 yd³ = 27 ft³ |
| Recommended overage | +10% |
Aggregate subtypes & their densities
| Subtype | Density |
|---|---|
| MOT Type 1 / road base | 1.5 tons/yd³ |
| Crushed stone aggregate | 1.4 tons/yd³ |
| Pea gravel | 1.4 tons/yd³ |
| Recycled concrete aggregate | 1.35 tons/yd³ |
Source: Typical construction aggregate bulk density (~1.3–1.7 tons/yd³), per Omni Calculator. Densities vary with moisture and compaction — the weight figure is an estimate.
How much aggregate do you need?
"Aggregate" is the umbrella term for the crushed rock, gravel, sand, and recycled material that forms the compacted sub-base under driveways, patios, paths, and slabs. The job of an aggregate layer is to spread load and drain water away from whatever sits on top, so it almost always goes down compacted, in lifts, over a firm subgrade.
For a graded sub-base that packs solid, use a dense, well-graded aggregate (MOT Type 1 or a crusher-run road base) that blends coarse stone with fines. Where you need drainage instead of a hard surface — under a permeable patio, say — use a clean single-size stone. Recycled concrete aggregate is a cheaper, greener option that performs much like virgin crushed stone for most sub-base work.
Suppliers sell aggregate by the ton (bulk, delivered) or in bags for small jobs. Use the tons figure when you order in bulk, and remember aggregate compacts — the loose volume you buy settles once it is tamped, which is why you order around 10% extra.
Frequently asked questions
How much aggregate do I need?+
Multiply your area (length × width in feet) by your depth in feet for cubic feet, divide by 27 for cubic yards, then multiply by about 1.4 for US tons. Enter your numbers above and the calculator works it out instantly.
What is aggregate in construction?+
Aggregate is the granular material — crushed stone, gravel, sand, or recycled concrete — used as a compacted sub-base under driveways, patios, paths, and slabs, and as a component of concrete. It spreads load and helps drainage.
How many tons of aggregate are in a cubic yard?+
About 1.4 tons per cubic yard for typical aggregate, ranging from roughly 1.3 to 1.7 tons depending on the material and how well it is compacted. Graded road bases sit at the heavier end.
How deep should an aggregate sub-base be?+
For a residential driveway or patio sub-base, lay 4–6 inches of aggregate compacted in 2–3 inch lifts. Footpaths and lightly used areas need 2–3 inches; areas carrying vehicles or soft ground may need up to 8 inches.
What is MOT Type 1 aggregate?+
MOT Type 1 is a well-graded crushed limestone or granite that blends coarse stone down to fine dust, so it compacts into a dense, strong, free-draining sub-base. It is the standard sub-base material for driveways and patios.
How much does a cubic yard of aggregate weigh?+
About 2,600–3,400 lb (1.3–1.7 US tons), depending on the aggregate type and moisture. The calculator uses 1.4 tons per cubic yard as a general figure.
Can I use recycled aggregate for a sub-base?+
Yes. Recycled concrete aggregate compacts and performs much like virgin crushed stone for most driveway, patio, and path sub-bases, and it is usually cheaper and lower-carbon. Pick the recycled subtype above for a closer weight estimate.
How much area does a ton of aggregate cover?+
About a cubic yard of aggregate (≈1.4 tons) covers 81 sq ft at 4 inches deep, 108 sq ft at 3 inches, or 162 sq ft at 2 inches. Set your real depth above to see the exact coverage.
Should I order extra aggregate?+
Yes — add about 10% for compaction and spillage, and 15% over soft or uneven ground where some of the layer settles into the subgrade.
Is this aggregate calculator free?+
Yes — free, no sign-up, and it runs entirely in your browser, so nothing you enter is stored or sent anywhere.