Class 5 Gravel Calculator
Calculate tons of Class 5 gravel for a driveway or road base using its 1.5 tons per cubic yard compacted density, plus total cost.
How this calculator works
Class 5 gravel is priced and delivered by the ton, so this calculator converts your area and depth into cubic yards, then multiplies by Class 5’s compacted density of 1.5 tons per cubic yard — the same density used for crusher run, since both are graded aggregate-and-fines road-building mixes.
Formula: Cubic yards = (Length ft × Width ft × Depth ft) ÷ 27. Tons = Cubic yards × 1.5.
Worked example
A 20 ft × 10 ft driveway section at a 6-inch depth:
- Depth in feet: 6 ÷ 12 = 0.5 ft
- Cubic yards: (20 × 10 × 0.5) ÷ 27 ≈ 3.7037 yd³
- Tons: 3.7037 × 1.5 ≈ 5.56 tons
- At $30/ton, that’s $166.67 before waste.
Coverage reference
| Area | Tons needed (at 6 in) |
|---|---|
| 10 ft × 5 ft | 1.39 tons |
| 20 ft × 10 ft | 5.56 tons |
| 40 ft × 20 ft | 22.22 tons |
How to measure your area
Measure the full length and width of the driveway or road footprint in feet, including a few extra inches of width on each side if your local spec calls for base extending past the finished surface edge. Use the compacted target depth from your project’s spec, not the loose depth you’ll spread before compacting.
Frequently asked questions
What is Class 5 gravel?
Class 5 gravel is a graded aggregate-and-fines road base mix defined by state specifications common across the Upper Midwest, particularly Minnesota Department of Transportation (MnDOT) standards. It blends crushed rock or gravel with a controlled percentage of fines so it compacts into a dense, stable road-building layer.
How is Class 5 different from crusher run or road base sold elsewhere?
They're functionally similar graded aggregate-and-fines blends, and Class 5 shares crusher run's 1.5 tons per cubic yard compacted density, but "Class 5" refers specifically to the gradation spec used in MnDOT-region contracts, while "crusher run" and "road base" are more generic regional names for comparable material elsewhere in the country.
Is there a Class 5Q or modified Class 5?
Yes — some suppliers offer Class 5Q (quarried, from bedrock rather than glacial gravel deposits) which tends to be more angular and consistent, or modified blends with a different fines percentage for specific drainage or strength requirements. Ask your supplier which variant matches your project's spec if it's called out.
What depth of Class 5 gravel is typical for a driveway?
4-6 inches compacted is standard for a residential driveway base in regions that spec Class 5, with deeper sections (8 inches or more) common on gravel roads or areas that see heavy vehicle traffic, especially where frost heave is a concern.
Do I need to compact Class 5 gravel in lifts?
Yes, for anything past about 4 inches. Spreading and compacting in 3-4 inch lifts gets a denser, more uniform result than trying to compact one thick lift, where the bottom portion often stays under-compacted.
Should I add waste when ordering Class 5 gravel?
Yes, the 10% waste toggle is a reasonable allowance for compaction settling and an uneven excavated subgrade, both common on driveway and road-base jobs.
Estimates only. Verify quantities with your supplier before purchasing.