Aggregate Calculator
Calculate how much aggregate, gravel or crushed stone you need. Enter length, width and depth to get volume in yd³ and weight in tons and tonnes instantly.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Aggregate Calculator Works
This calculator tells you how much aggregate — gravel, crushed stone or road base — you need to fill an area to a chosen depth. Enter the length, width and depth of the area and it returns the volume in cubic feet and cubic yards, plus the weight in US tons and metric tonnes.
The Formula
Aggregate is sold by volume (cubic yards) and by weight (tons or tonnes). Both come from the same base calculation:
Volume (ft³) = length × width × depth (all in feet) Volume (yd³) = Volume (ft³) ÷ 27 Weight (lb) = Volume (ft³) × density Weight (US tons) = Weight (lb) ÷ 2000
The density of crushed stone and gravel is about 105 lb/ft³, which works out to roughly 1.4 tonnes per cubic yard.
Worked Example
For an area 20 ft long, 10 ft wide, filled 4 inches deep:
- Depth in feet = 4 ÷ 12 = 0.333 ft
- Volume = 20 × 10 × 0.333 = 66.7 ft³ = 2.47 yd³
- Weight = 66.7 × 105 = 7,000 lb = 3.5 US tons (about 3.18 tonnes)
Choosing the Right Depth
The depth of an aggregate layer depends on the job:
- Footpaths and patios: 3–4 inches of compacted base
- Garden gravel: 2–3 inches over a weed membrane
- Driveways: 6–8 inches (often in two compacted layers)
Why Order a Little Extra
Aggregate compacts when rolled or driven on, and some is always lost to spillage and uneven ground. Adding 5–10 percent to the calculated amount avoids a second delivery and the call-out fee that comes with it.
| Area & depth | Volume | Approx. weight |
|---|---|---|
| 20 × 10 ft @ 4 in | 2.47 yd³ | ≈ 3.5 US tons |
| 30 × 12 ft @ 3 in | 3.33 yd³ | ≈ 4.7 US tons |
| 40 × 20 ft @ 6 in | 14.8 yd³ | ≈ 21 US tons |
Frequently asked questions
How do I calculate how much aggregate I need?+
Multiply length × width × depth (all in feet) to get the volume in cubic feet, then divide by 27 for cubic yards. Multiply the cubic feet by the density (about 105 lb/ft³ for crushed stone) and divide by 2000 to get US tons.
How many tons of aggregate are in a cubic yard?+
A cubic yard of dry crushed stone weighs roughly 1.3 to 1.5 US tons (about 1.4 tonnes), depending on stone size and moisture. One cubic yard is 27 cubic feet, so at 105 lb/ft³ that is about 2,835 lb, or 1.42 tons.
What density should I use for aggregate?+
Crushed stone and gravel are typically 95 to 110 lb/ft³, so 105 lb/ft³ is a good default. Sand is lighter at about 100 lb/ft³ and wet or compacted material is heavier. Adjust the density field for your specific aggregate.
How deep should an aggregate base be?+
A patio or path sub-base is usually 4 inches of compacted aggregate, while a driveway base is often 6 to 8 inches. Enter your planned depth in inches and the calculator converts it for you.
Should I order extra aggregate?+
Yes. Add 5 to 10 percent extra to cover compaction, uneven ground and waste. The calculator shows the exact volume, so multiply the result by 1.05 to 1.10 when placing your order.