Laying gravel for a driveway, walkway, or garden path? Just enter your dimensions and depth, and our free gravel calculator tells you exactly how much you need โ in cubic yards, tons, and even how many bags. It handles rectangles, circles, and irregular shapes so you order the right amount every time.
Modify the values and click the calculate button to use
Area to Cover:
A gravel calculator figures out the volume of gravel you need for a project. You give it three numbers: length, width, and depth. It spits out the amount in cubic yards or tons.
Here's the formula our calculator uses:
Length (ft) ร Width (ft) ร Depth (ft) = Cubic Feet
Then we convert cubic feet to cubic yards (because gravel is sold by the cubic yard).
Cubic Feet รท 27 = Cubic Yards
Why 27? Because a cubic yard is 3 feet ร 3 feet ร 3 feet. That's 27 cubic feet. Simple.
But wait. Most people don't measure depth in feet. You measure it in inches. So you need to convert inches to feet first. Just divide your depth in inches by 12. For example: 4 inches deep รท 12 = 0.33 feet. See? Not so bad.
Let's walk through a real example. Say you're putting gravel on a driveway that's 20 feet long and 10 feet wide. You want it 4 inches deep.
Measure the length and width in feet. Length = 20 feet. Width = 10 feet.
Measure the depth in inches, then convert to feet. Depth = 4 inches. 4 รท 12 = 0.33 feet.
Multiply them together. 20 ร 10 ร 0.33 = 66 cubic feet.
Convert to cubic yards. 66 รท 27 = 2.44 cubic yards.
So you need about 2.5 cubic yards of gravel. But here's where most people mess up.
Most people forget about compaction. When you pour gravel, it settles. The rocks shift and fill in gaps. So your 4-inch layer might end up being 3.5 inches after a few weeks.
To fix this, add 10-15% to your total. So instead of 2.5 cubic yards, order 2.75 or even 3 cubic yards. You'll thank yourself later.
Another common mistake? Measuring in inches instead of feet. If you measure your driveway as 240 inches long (which is 20 feet), and you don't convert, your calculator will give you a crazy number. Always measure in feet.
Your driveway isn't a perfect rectangle? No problem. Just break it into smaller rectangles.
Say your driveway is L-shaped. Measure the long part as one rectangle. Measure the short part as another rectangle. Calculate each one separately. Then add them together.
For circular areas (like a fire pit):
Radius (ft) ร Radius (ft) ร 3.14 ร Depth (ft) = Cubic Feet. Then divide by 27 to get cubic yards. Easy.
Here's something most calculators don't tell you: different gravel types weigh different amounts. A cubic yard of pea gravel weighs about 1.4 tons. But a cubic yard of crushed stone weighs about 1.6 tons.
Why does this matter? Because suppliers sell by the ton, not the cubic yard. So you need to convert.
Here's a quick guide:
So if our calculator says you need 2.5 cubic yards of crushed stone, you'd order 2.5 ร 1.6 = 4 tons. Always ask your supplier what type of gravel they're selling and what it weighs. They'll know.
This depends on what you're using it for. Here are the standard depths:
Remember: deeper is usually better. You can always add more gravel later, but it's a pain. So go a little deeper than you think.
Here's a trick I learned from a landscaper. After you spread your gravel, stick your hand into it. If your fingers touch the ground underneath, it's too thin. You need at least 2 inches of gravel to cover your hand.
For driveways, use your whole hand. If your palm touches the ground, add more gravel. Simple.
This is a big one. For driveways and patios, you need two layers:
๐ชจ Base Layer
The bottom layer. Made of larger, angular rocks (like #3 crushed stone). Usually 4-6 inches deep. Provides drainage and stability.
โจ Top Layer
What you see. Made of smaller, smoother rocks (like pea gravel or #57 stone). Usually 2-3 inches deep. Looks nice and comfortable to walk on.
So for a driveway, you might need 6 inches of base gravel and 3 inches of top gravel. That's 9 inches total. Most calculators don't tell you this. But now you know.
When you call a supplier, they'll ask for two things: the type of gravel and the amount in tons. Here's how to handle that conversation:
Use our calculator to get the cubic yards.
Multiply by the weight per cubic yard (see the table above).
Add 10-15% for compaction and waste.
Tell the supplier: "I need 4 tons of #57 crushed stone."
They'll deliver it. Easy.
Problem: My gravel keeps sinking into the mud.
Solution: You need a base layer. Put down landscape fabric first, then add 4-6 inches of base gravel. The fabric keeps the gravel from mixing with the soil.
Problem: My gravel looks too thin.
Solution: Use the hand test. If your fingers touch the ground, add more gravel. You probably need another inch or two.
Problem: My gravel is spreading everywhere.
Solution: You need edging. Install metal or plastic edging around the perimeter to keep the gravel in place.
Problem: My pea gravel is hard to walk on.
Solution: Pea gravel shifts under your feet. For walkways, use crushed stone instead. It locks together and stays put.
Here's the thing: gravel settles. It compacts. It gets kicked around. And your ground is probably not perfectly level.
So always order 10-15% more than the calculator says. If you have extra, you can use it for another project. If you run short, you'll have to order more and pay another delivery fee. Trust me, it's better to have too much.
Did you know that gravel is one of the oldest building materials? Humans have been using it for thousands of years. The Romans used gravel for their roads. Some of those roads are still around today.
So when you lay gravel, you're doing something ancient. Pretty cool, right?
Gravel mining has an impact on the environment. It uses energy and creates dust. So using the right amount isn't just about saving money. It's about reducing waste.
Our calculator helps you get it right the first time. No extra trips to the supplier. No wasted gravel.
Using a gravel calculator is easy. But understanding what it tells you? That's the real skill. Now you know how to measure, how to convert, and how to order. You know about compaction, base layers, and the hand test. You're ready.
So go ahead. Use our calculator. Order your gravel. And build something awesome.
Determine the area to cover and desired depth. A minimum of 2-4 inches is a workable baseline for most projects. Multiply area by depth for volume, then use density to find weight. Here's a quick reference:
Measure Area
Length ร Width in feet gives you square footage.
Calculate Volume
Area ร Depth (in feet) = Cubic Feet. Divide by 27 for cubic yards.
Convert to Tons
Multiply cubic yards by gravel density (1.4-1.6 tons/yard).
Measure the length and width of your driveway in feet. Then decide how deep you want the gravel (4-6 inches is standard for driveways). Convert the depth to feet by dividing by 12. Then multiply length ร width ร depth. That gives you cubic feet. Divide by 27 to get cubic yards. Then add 10-15% for compaction. Our calculator does all this for you.
For a 20ร20 driveway at 4 inches deep, you need about 4.9 cubic yards of gravel. That's roughly 7.8 tons of crushed stone (at 1.6 tons per cubic yard). But remember to add 10-15% for compaction, so order about 9 tons. Always check with your supplier for exact weights.
Pea gravel is smooth, rounded, and shifts underfoot โ good for decoration. Crushed stone is angular, locks together, and stays put โ better for driveways and walkways. Pea gravel weighs about 1.4 tons per cubic yard; crushed stone about 1.6 tons.
2-3 inches is standard for walkways. If you're using it as a base layer, go 4-6 inches. Always add a little extra for compaction and settling.
Yes, for most projects. Landscape fabric prevents gravel from mixing with soil, stops weeds from growing through, and improves drainage. It's especially important for driveways and areas with soft soil.
Multiply cubic yards by the gravel's weight per cubic yard. Pea gravel = 1.4 tons/yard. Crushed stone = 1.6 tons/yard. So 3 cubic yards of crushed stone = 3 ร 1.6 = 4.8 tons.
You can, but it's not ideal. Pea gravel shifts and doesn't compact well. For driveways, use crushed stone (#57 or #3) as a base layer, with a thinner top layer of smaller gravel if desired.
One cubic yard of gravel covers about 100 square feet at 3 inches deep, or 80 square feet at 4 inches deep. Coverage decreases as depth increases.
This happens when gravel mixes with soft soil underneath. Install landscape fabric before laying gravel, and use a base layer of larger, angular rock for stability.
Install edging โ metal, plastic, or brick โ around the perimeter. This creates a barrier that keeps gravel contained. Also, crushed stone stays in place better than pea gravel.
Suppliers typically sell by the ton. Our calculator gives you cubic yards first, then you convert to tons using the gravel type's weight. Always confirm with your supplier how they price it.
Crushed stone (#57 or #3) is usually the most economical, costing $25-$50 per ton delivered. Pea gravel and river rock are more decorative and cost $35-$65 per ton. Prices vary by location.
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