38 free calculators for trades and homeowners

Landscaping & Outdoor

Gravel Driveway Calculator

Base and surface course tonnage for a gravel driveway, built up in the two layers a drive actually needs.

Your measurements

Driveway
Add any apron, turning circle or parking bay outside the main run.
Build up
Larger stone at the bottom. Go deeper on clay or where trucks will use the drive.

Your result

Sample values

19.8

Tons total

13.2

Tons of base course

6.6

Tons of surface course

14.67

Cubic yards total

60 × 12 ft drive, 4 in base and 2 in surface, 10% waste.

What to order

Layer Quantity
Base — #2 or 21AA 13.2 tons
Surface — #57 or crusher run 6.6 tons
Geotextile fabric 750 ft²
Tri-axle loads 2 loads

How to use this calculator

Measure the driving surface and add any apron or turning area separately. Then set the two depths: a coarser base that carries the load and a finer surface that gives you something comfortable to drive and walk on.

A single deep layer of one stone size is a common mistake. Large clean stone alone stays loose and rutted; fine stone alone pushes into the subgrade. The two-layer build is what makes a gravel drive last.

Formula

Area = (Length × Width) + Parking

Layer volume = Area × Layer depth

Tons = Volume × Density ÷ 2,000

Density
about 100 lb/ft³ for crushed stone

Each layer is calculated separately because the grades differ.

Worked example

A 60 ft by 12 ft drive, 4 in base and 2 in surface, 10% waste.

  1. 60 ft × 12 ft = 720 ft²
  2. Base: 720 × 0.333 ft = 240 ft³, × 1.10 = 264 ft³
  3. 264 ft³ × 100 lb = 26,400 lb, or 13.2 tons
  4. Surface: 720 × 0.167 ft = 120 ft³, × 1.10 = 132 ft³
  5. 132 ft³ × 100 lb = 13,200 lb, or 6.6 tons
  6. Total 19.8 tons, or 14.67 yd³

19.8 tons in total, split 13.2 base and 6.6 surface

Understanding your results

Twenty tons is two truck loads, so it is worth ordering both layers at once and having the base spread before the surface arrives. Splitting delivery across weeks means paying two delivery charges and driving on an unfinished base in between.

Build a crown into the middle of the drive, about an inch of rise for every four feet of width. Water that runs off the sides never gets the chance to sit in a wheel rut, and rutting is what kills a gravel drive.

Questions

About this calculator

Ask something else

Six inches total over firm ground, split between a coarser base and a finer surface. Soft or clay ground wants eight to twelve inches and a geotextile beneath. Anything under four inches will rut the first time a delivery truck uses it.

Expect to add a thin surface layer every three to five years, sooner where vehicles turn or brake. Raking the high spots back into the ruts once a year extends that considerably and costs nothing but time.

On anything steeper than about ten percent, yes, unless you use an angular crusher run that locks together and add cross drains to take water off the surface. Rounded pea gravel on a slope migrates downhill and should be avoided.

It is not essential but it holds the depth. Without a restraint the stone spreads sideways into the grass over a few years, the drive gets wider and thinner, and the middle needs topping up sooner.

Keep going

All Landscaping & Outdoor tools
Estimates, not specifications. Results are based on the values you enter and on typical material properties. Densities, coverage rates and product sizes vary between suppliers, so confirm quantities against your supplier's data before ordering. Structural work must be signed off by a qualified professional and meet your local building code.