Crushed Stone Calculator — Compacted Yards and Tons
Plan angular crushed aggregate for a compacted base or drainage course, including the loose-to-compacted volume difference.
What does the crushed stone calculator calculate?
Crushed stone orders should start with the compacted finished volume, not the size of the loose delivery pile. This calculator increases finished cubic yards by a compaction allowance and waste, then applies the entered loose density. Use the supplier’s gradation-specific density because crusher run and clean stone differ.
Loose crushed stone order formula
Angular aggregate loses apparent volume when compacted. The calculation first establishes finished compacted geometry, then estimates the additional loose product required for densification and handling.
How to measure for an accurate estimate
- Measure each course independently when a section includes different aggregate gradations.
- Enter the design’s compacted thickness, not the depth of freshly spread loose stone.
- Average several widths for flared sections or divide them into rectangles and triangles.
- Obtain loose bulk density and expected shrinkage from the quarry or testing data.
Compacted patio base
A 30 ft by 10 ft base is 4 in compacted, with 15% compaction allowance, 5% waste, and 1.5 tons/yd³.
The finished volume is 3.70 yd³; order about 4.47 loose yd³, estimated at 6.71 tons.Before you purchase material
- Specify gradation and intended use; similarly named crushed products are not interchangeable.
- Ask whether the quoted tonnage is based on moist scale weight and whether delivery minimums apply.
- Plan delivery, grading, water, and compaction equipment together to avoid an exposed unfinished lift.
- Order separate clean drainage stone and dense-graded base rather than blending their quantities.
Common questions
What density should I use for crushed stone?
Use the quarry’s loose bulk density for the exact gradation and moisture condition. If none is available, 1.5 tons per cubic yard is a planning assumption, not a purchasing guarantee. Clean, uniformly sized stone can have more void space than dense-graded aggregate.
What is the difference between crushed stone and gravel?
Crushed stone is mechanically broken and typically angular, while natural gravel may have smoother rounded particles. Angular, well-graded material can interlock under compaction. Product names vary regionally, so specify gradation, fines content, and intended application instead of relying on terminology.
How much does crushed stone compact?
There is no universal percentage. Gradation, moisture, placement thickness, equipment, and target density all matter. Fifteen percent is a useful preliminary allowance for loose volume, but a supplier or geotechnical specification should provide the job-specific relationship for structural work.
Can I compact crushed stone in one thick layer?
Usually, aggregate is placed in controlled lifts so compaction energy reaches the full thickness. Maximum loose lift thickness depends on material, equipment, moisture, and specification. Follow the project requirements or local professional guidance; the calculator does not design the compaction procedure.
Sources and reference standards
- Federal Highway Administration — Gravel Roads Construction and Maintenance GuideFederal guidance on aggregate selection, placement, moisture, and compaction.
- National Institute of Standards and Technology — SI Units: VolumeFederal reference for volume units and unit relationships.