Gravel calculator: tons and yards for your driveway
The short answer
Cubic yards of gravel = length x width x depth, all in feet, divided by 27. For 1/4 to 2 inch gravel, tons = cubic yards x 1.42. A 300-foot driveway 12 feet wide and 4 inches deep takes about 44 yards, or 63 tons.
Gravel calculator
Use this gravel calculator to find the cubic yards and tons for a driveway, path or pad.
Your numbers
Your answer
About 44.4 cubic yards
You need about 44.4 cubic yards of gravel, or about 63.1 tons.
That is 300 by 12 feet at 4 inches deep.
- Cubic yards44.4
- Tons63.1
At a glance
- One cubic yard
- 27 cubic feet
- Gravel, 1/4 to 2 inch
- 1.42 tons a yard
- At 4 inches deep
- 1 yard covers 81 sq ft
- Once it packs down
- Can shrink 30% or more
How the gravel calculator works
- Multiply the length by the width, in feet. That is the area in square feet.
- Multiply the area by the depth in feet (inches divided by 12). That is cubic feet.
- Divide the cubic feet by 27 to get cubic yards.
- For a driveway, if you enter extra for packing down, multiply the yards by 1 plus that percent.
- Multiply the cubic yards by the material's tons per cubic yard to get tons.
- For truckloads, divide the cubic yards by what one load holds, and round up.
What it assumes
- The area is a rectangle with the same depth all over. For a driveway that curves, measure its length along the middle.
- Weights are the figures in New Mexico's state conversion table. Rock from your supplier may weigh more or less. If the yard gives you its own tons per yard, pick "My supplier's number" and use that.
- No extra is added unless you enter it.
Cubic yards to tons
Gravel is sold by the ton or by the cubic yard. To go from yards to tons, multiply by the weight per yard. To go from tons to yards, divide by it.
| Material | Tons per cubic yard | Cubic yards per ton |
|---|---|---|
| Gravel, 1/4 to 2 inch | 1.42 | 0.70 |
| Pit run gravel | 1.62 | 0.62 |
| Base course | 1.25 | 0.80 |
| Sand | 1.45 | 0.69 |
| Topsoil | 0.80 | 1.25 |
| Fill dirt | 0.80 | 1.25 |
So 20 tons of 1/4 to 2 inch gravel is about 14 cubic yards (20 divided by 1.42). Going the other way, 10 yards of it weighs about 14.2 tons.
Gravel driveway calculator: a Bonners Ferry example
Say you are putting new gravel on a 300-foot driveway outside Bonners Ferry. It is 12 feet wide, and you want 4 inches of 1/4 to 2 inch gravel.
- Area: 300 x 12 = 3,600 square feet.
- Cubic feet: 3,600 x 4 / 12 = 1,200 cubic feet.
- Cubic yards: 1,200 / 27 = 44.4 cubic yards.
- Tons: 44.4 x 1.42 = 63.1 tons.
- If your hauler's truck holds 10 cubic yards: 44.4 / 10 = 4.4, so 5 loads.
New driveway onto a county road?
Before you build a new driveway onto a county road, you need a permit from Boundary County.
You may not need a pro
Spreading a few yards on a path or a shop pad is a job for a shovel, a wheelbarrow and a rake. A long driveway is different. It takes a truck to haul the gravel and a machine to spread it, and that is where an excavation business comes in.
Facts this tool uses
| Fact | Figure | Source |
|---|---|---|
| Weight per cubic yard | Gravel 1/4 to 2 inch 1.42 tons; pit run 1.62; base course 1.25; sand 1.45; topsoil 0.8; fill dirt 0.8 (short tons) | New Mexico Energy, Minerals and Natural Resources Dept., Conversion factors for construction materialsTable checked Oct 28, 2026 (adapted by the state from BLM Handbook H-3890-1) |
| Gravel packs down | Ordinary compaction can cut the volume by 30% or more in many parts of the country | FHWA and SD LTAP, Gravel Roads Maintenance and Design ManualCalculating Quantity section checked Oct 28, 2026 |
| Driveway onto a county road | A permit is required before building any approach or access onto a Boundary County road; no fee | Boundary County Road and Bridge, Approach permitsApproach permits page checked Oct 28, 2026 |
Next step
Want it hauled and spread for you? Excavation businesses in Bonners Ferry