Gravel Calculator
Tons and cubic yards of gravel for driveways and paths.
What it does
Gravel sells by weight while driveways measure by volume, and density bridges them. Crushed stone packs near 1.4 tons per cubic yard, so a two car driveway at four inches deep already weighs over ten tons.
The tool above takes length, width, and depth in imperial or metric with a compaction allowance. It returns tons or tonnes, volume, and cost at your price.
Depth decides lifespan more than stone size. Thin scatter over mud ruts in one winter, while six compacted inches over fabric carry cars for years. Layers beat single deep dumps because each lift compacts properly.
Stone type moves density and price together. Crushed angular rock locks and weighs more per yard than rounded pea gravel, which shifts under tires and covers less per ton.
How to use
- Switch the unit system first: imperial for feet and tons, metric for meters and tonnes.
- Measure the drive at its longest and widest.
- Pick depth: 4 inches for refresh, 6 to 8 for new builds.
- Keep the compaction allowance and confirm truck minimums.
Formula
- 1.4 tons/yd3
- Compacted crushed stone density used here.
- 1.6 t/m3
- Metric twin of the same density.
- waste
- Compaction and spillage share as a rate.
Round rock and sand run lighter per volume, so the same math with 1.2 to 1.3 factors fits them. Quarries quote exact densities per product when precision matters.
Worked example
Example: 50 x 12 ft driveway, 4 inches deep
Drive 50 by 12, depth 4 inches, 5% allowance, $55 per ton.
- Volume: 50 x 12 x (4/12) = 200 ft3.
- With allowance: 200 x 1.05 = 210 ft3.
- Yards: 210 / 27 = 7.78 yd3.
- Tons: 7.78 x 1.4 = 10.89 tons, shown as 10.89.
- Cost: 10.89 x $55 = $598.89 before delivery.
Reference table
| Length | Volume | Tons |
|---|---|---|
| 25 ft | 3.89 yd3 | 5.44 tons |
| 50 ft | 7.78 yd3 | 10.89 tons |
| 75 ft | 11.67 yd3 | 16.33 tons |
| 100 ft | 15.56 yd3 | 21.78 tons |
Limits
- Crushed stone density assumed. Products vary.
- Flat math. Crowned drives shed a little volume.
- Soft subgrade eats extra stone beyond allowance.
- Delivery minimums and fees excluded.
Common mistakes
- Ordering yards when the quarry sells tons, or reverse.
- Spreading 2 inches over mud and expecting years.
- Dumping full depth in one lift without compacting.
- Skipping fabric over soft clay.
- Forgetting the short load fee under truck minimums.
Try it yourself
Quick checks. Answers sit tucked under each question.
20 x 10 ft path, 3 inches, no waste. Tons?
20 x 10 x 0.25 = 50 ft3 = 1.85 yd3. Then 1.85 x 1.4 = 2.59 tons.
Same path metric: 6 x 3 m, 8 cm. Tonnes?
6 x 3 x 0.08 = 1.44 m3. Then 1.44 x 1.6 = 2.30 tonnes.
Questions
How deep should a gravel driveway be?
Six to eight inches compacted in lifts for new builds, four for refreshes over solid base.
Tons or yards: which do quarries use?
Usually tons at the scale house. Convert with 1.4 tons per yard for crushed stone.
How much does a dump truck hold?
Ten to twenty plus tons by truck size. Small jobs trigger short load fees.
Crushed stone or pea gravel?
Crushed locks under tires. Pea gravel looks soft but migrates and ruts.
Do I need landscape fabric?
Over clay and soft soil, yes. It separates stone from mud that would swallow it.
How often to top up?
Every few years with grading. Potholes want fill plus compaction, not scatter.