Road Base Calculator
Calculate the tons of road base needed under driveways, pads and paths.
What you'll need to order
- crusher run / road base
- geotextile fabric
- compaction plate rental
Prices vary by region and haul distance. Get quotes from at least two local suppliers.
How this calculator works
tons = length × width × (depth ÷ 12) × 135 ÷ 2000
Compacted road base weighs about 135 lb per cubic foot, roughly 3,645 lb per cubic yard — noticeably denser than clean stone because the fines fill the voids. This figure is for the compacted depth you want to end up with.
Worked example
With length 10 ft, width 10 ft, compacted depth 4 in, this calculator returns 2.25 tons.
Frequently asked questions
How much road base do I need for a driveway?
A 40 by 12 ft driveway at 6 inches compacted depth needs about 16 tons. Multiply area by depth in feet, multiply by 135, then divide by 2,000.
How thick should road base be under a driveway?
Four to six inches for cars on firm soil, 8 to 12 inches where trucks park or the subgrade is clay. Soft ground needs geotextile fabric underneath as well, or the base will pump down into the soil.
What is the difference between road base and crushed stone?
Road base, also sold as crusher run or dense-grade aggregate, contains stone dust and fines that let it lock together and compact hard. Clean crushed stone has the fines washed out — it drains better but stays loose and cannot form a structural base.
How many lifts should road base go down in?
Compact in layers of 4 inches or less. A 6 inch base means two passes, an 8 inch base means two, and 12 inches means three. Dumping the full depth and compacting once leaves the bottom loose, which is the most common cause of driveway failure.
How much does a yard of road base weigh?
About 3,600 lb, or 1.8 tons, compacted. That is heavier than most aggregates, so a tandem dump truck legally carries around 8 cubic yards rather than the usual 10 to 14.