Gravel Calculator
Find how many cubic yards, tons and bags of gravel your driveway, path or base layer needs. Enter the area and depth, pick the stone type, and add a small waste allowance for settling.
| Detail | Result |
|---|---|
| Area covered | 200 sq ft |
| 50 lb bags (about) | 109 |
| Estimated cost | $109 |
See more of Backyard Calculators on Google
Add us as a preferred source to see our calculators and guides more often in Google Top Stories.
Was this calculator helpful?
How Gravel Calculator Works
Four quick steps happen behind the screen every time you change a number.
Finds the area
Length times width gives the surface you need to cover, in square feet.
Turns depth into volume
Depth in inches is divided by 12, so the area becomes cubic feet of stone.
Adds a settling allowance
Loose stone packs down once it is walked or driven on, so a small percentage is added on top.
Converts to weight
Cubic yards are multiplied by the density of your stone, because suppliers often sell gravel by the ton.
How to Use Gravel Calculator
Five quick steps take you from a tape measure to a usable result.
- Measure the areaUse a tape to get the length and width of the driveway, path or bed.
- Pick the depthChoose 2 to 3 inches for paths, 4 inches for a driveway top layer and 6 inches or more for a base.
- Select your stoneEach stone type weighs a different amount per cubic yard, so choose the one you plan to buy.
- Keep the settling allowanceFive percent suits most jobs. Raise it for soft ground or a sloped site.
- Read cubic yards and tonsOrder by the unit your supplier uses, and add your price per ton to see a cost estimate.
Formula Used in Gravel Calculator
These are the standard formulas behind every result, so you can check the numbers yourself.
Volume
L and W are in feet, D is in inches, and V is in cubic yards.
With settling
A 5 percent allowance means you multiply by 1.05.
Weight
Density is the tons per cubic yard of your stone type.
Worked example
A 20 ft by 10 ft path laid 3 inches deep needs 20 × 10 × 3 ÷ 12 ÷ 27 = 1.85 cubic yards. With 5 percent extra that becomes 1.94 cubic yards, or about 2.72 tons of crushed stone.
Gravel Coverage Chart
How far one cubic yard of gravel goes at common depths. Use it to size a quick order.
| Depth | Sq ft per cu yd | Cu yd per 100 sq ft |
|---|---|---|
| 1 inch | 324 | 0.31 |
| 2 inches | 162 | 0.62 |
| 3 inches | 108 | 0.93 |
| 4 inches | 81 | 1.23 |
| 6 inches | 54 | 1.85 |
| 8 inches | 40 | 2.47 |
Figures are before any settling allowance. One cubic yard is 27 cubic feet.
Gravel Needed by Area
Cubic yards and tons of crushed stone for common driveway and path sizes at a 3 inch depth.
| Size | Cu yd | Tons | 50 lb bags |
|---|---|---|---|
| 10 × 10 ft | 0.97 | 1.36 | 55 |
| 10 × 20 ft | 1.94 | 2.72 | 109 |
| 12 × 24 ft | 2.8 | 3.92 | 157 |
| 12 × 40 ft | 4.67 | 6.53 | 262 |
| 15 × 50 ft | 7.29 | 10.21 | 409 |
| 20 × 60 ft | 11.67 | 16.33 | 654 |
Based on crushed stone at 1.4 tons per cubic yard, 3 inches deep and 5 percent extra.
Common Gravel Mistakes
Four slips that throw off the result, and how to avoid them.
Forgetting the depth unit
Depth is entered in inches while length and width are in feet. Mixing them up changes the answer twelve times over.
Ordering the exact figure
Loose stone compacts under foot and tyres. Without a settling allowance the surface ends up thin.
Using one density for every stone
Pea gravel, crushed stone and decomposed granite weigh different amounts. Choose the right type before reading tons.
Skipping the base layer
A 3 inch top layer on bare soil sinks and mixes with dirt. Plan a compacted base under it for driveways.
Tools You Must Know
One number is rarely enough for a yard project. These calculators pair well with this one.
Gravel Calculator FAQs
Quick answers before you order materials.
How do I calculate how much gravel I need?
Multiply length by width by depth in feet, then divide by 27 to get cubic yards. The calculator does this for you and adds a settling allowance.
How many square feet does one cubic yard of gravel cover?
At a 3 inch depth, one cubic yard covers about 108 square feet. At 2 inches it covers about 162 square feet.
How deep should a gravel driveway be?
A top layer of 4 inches over a compacted base works for most driveways. Paths and garden beds usually need 2 to 3 inches.
How many tons are in a cubic yard of gravel?
Crushed stone weighs about 1.4 tons per cubic yard. Pea gravel is close to 1.35 and decomposed granite near 1.5.
Should I order extra gravel?
Yes. Five percent covers settling on firm ground, and 10 percent is safer on soft or uneven sites.
Is the Gravel Calculator free?
Yes. It is free to use, and it works in feet and inches or in metres and centimetres.
Browse Our Categories
Explore every calculator by project type, from decks and fences to pools and gardens.