Start with the right measurement
A gravel estimate depends on the compacted layer you want, not just the area. Enter the target depth, choose an allowance for handling and compaction, and edit density when your supplier provides a product-specific value.
How to use this calculator
- 01Area and depth: Finished length, width, and compacted layer depth.
- 02Waste/compaction allowance: An explicit allowance for settling, trimming, and handling.
- 03Density: Editable bulk density supplied by the quarry or bag label when available.
Volume is the geometric quantity. Weight is only an estimate because density changes with rock type, grading, moisture, and how tightly the layer is compacted.
Units: Imperial depth is entered in inches and density in pounds per cubic yard. Metric depth is in centimetres and density in kilograms per cubic metre.
How the calculation works
Volume = length × width × depth × quantity. Weight = planned volume × density.A 20 × 10 ft area, 3 in deep, contains 50 ft³ or about 1.85 yd³ before waste.
Worked examples
Driveway base
- Measure a 24 × 12 ft driveway zone.
- Use a 6 in compacted depth, or 0.5 ft.
- Calculate 144 ft³ = 5.33 yd³, then add the chosen allowance.
Result: The volume is about 5.33 yd³ before density converts it to an estimated weight.
Garden path
- Use a 30 ft × 3 ft path at 2 in depth (0.167 ft).
- Calculate 15 ft³, or about 0.56 yd³.
- Use your supplier’s bulk density rather than assuming driveway stone density.
Result: The smaller volume shows why a bagged product and a bulk delivery may produce different practical quantities.
How to measure
- 01Measure compacted target depth, not loose pile height.
- 02Use average dimensions where the excavation varies.
- 03Ask the supplier whether their density is loose, compacted, or a delivered bulk value.
Common mistakes to avoid
- Using the wrong density unit
- Ignoring compaction
- Assuming every gravel type weighs the same
Limits of this estimate
Default density is 2,800 lb/yd³ (1,661 kg/m³). Type, grading, moisture, and compaction change real weight.
Frequently asked questions
Why can I edit density?
Crushed stone, pea gravel, and wet material can have very different bulk densities.
Does waste include compaction?
Not automatically. Choose an allowance suitable for your material and installation.