How Much Concrete Do I Need for a Driveway? (Complete Guide)

The most common question I get about concrete driveways is “how much do I need?” The second most common question, usually asked after the first pour, is “why did I run short?”

After 20 years of pouring driveways, I can tell you the answer to both: people underestimate the volume and skip the waste factor. A driveway uses more concrete than most homeowners expect, and running short mid-pour means cold joints, weak spots, and a slab that looks patched instead of professional.

This guide walks through the full calculation, from measuring your driveway to ordering the right amount with proper waste allowance. If you want the quick answer, plug your dimensions into our concrete calculator and it’ll give you cubic yards in seconds.

Standard Driveway Dimensions

Before you calculate anything, you need accurate measurements. Here are the most common driveway sizes.

Single-Car Driveway

Width: 10-12 feet
Length: 20-50 feet (depends on distance from street to garage)
Typical area: 200-600 square feet

A 10-foot-wide driveway fits one car but feels tight. I recommend 12 feet minimum for comfortable door opening on both sides.

Two-Car Driveway

Width: 20-24 feet
Length: 20-50 feet
Typical area: 400-1,200 square feet

If you’re widening to fit two cars side by side, 20 feet is the absolute minimum. At 24 feet, both drivers can open doors without hitting each other.

Circular/Turnaround Driveway

Varies widely: 800-2,000+ square feet
Inside radius: Minimum 12 feet for passenger cars, 15+ feet for trucks

Circular driveways use significantly more concrete because of the extra width needed for the curve. Break these into sections (straight runs plus curved sections) for more accurate calculations.

Driveway Thickness: How Thick Should It Be?

This is where people get it wrong. A driveway is not a patio. It carries vehicle weight every single day, and the thickness needs to match.

4 Inches: Light Duty (Minimum)

Passenger cars and light trucks only
Requires excellent, well-compacted base
No heavy delivery trucks or trailers
The bare minimum I’d pour, and only on solid ground

5 Inches: Standard Residential (Recommended)

Cars, trucks, and SUVs
Occasional delivery truck or moving van
Good all-around choice for most homes
What I pour for 90% of residential driveways

6 Inches: Heavy Duty

Regular truck traffic, RVs, trailers, boats
Clay soil or areas with freeze-thaw cycles
Commercial entrances or shared driveways
Worth the extra concrete if you have any doubt about loads

My honest recommendation: Pour 5 inches. The cost difference between 4 and 5 inches is about 25% more concrete, but the strength increase is significant. I’ve torn out too many 4-inch driveways that cracked within five years because the homeowner wanted to save a few hundred dollars on the initial pour. Measure twice, cut once applies here too.

Step-by-Step: Calculating Cubic Yards for Your Driveway

Here’s the exact process I use on every driveway job.

Step 1: Measure Length and Width

Grab a tape measure and measure the actual driveway footprint. If your driveway changes width (common where it flares near the garage), break it into sections and measure each one.

Example: A straight driveway, 12 feet wide and 40 feet long.

Step 2: Calculate Square Footage

Length x Width = Square Footage

Example: 12 ft x 40 ft = 480 square feet

Step 3: Convert Thickness to Feet

Divide your thickness in inches by 12.

4 inches = 0.333 feet
5 inches = 0.417 feet
6 inches = 0.500 feet

Example (5-inch slab): 5 / 12 = 0.417 feet

Step 4: Calculate Cubic Feet

Square Footage x Thickness (in feet) = Cubic Feet

Example: 480 x 0.417 = 200.2 cubic feet

Step 5: Convert to Cubic Yards

Cubic Feet / 27 = Cubic Yards

Example: 200.2 / 27 = 7.41 cubic yards

Step 6: Add 10% for Waste

This step is non-negotiable. Multiply your cubic yards by 1.10.

Example: 7.41 x 1.10 = 8.15 cubic yards

For this 12x40 driveway at 5 inches thick, I’d order 8.5 yards of concrete.

Why You Always Order 10% Extra

New contractors and DIYers always ask if they can skip the waste factor. The answer is no. Here’s what that 10% covers:

Ground irregularities. Even with good base prep, your excavation isn’t perfectly flat. Low spots eat concrete.
Spillage during the pour. Concrete overflows chutes, spills off forms, and gets wasted at joints. It’s unavoidable.
Form movement. Stakes shift, boards bow slightly under pressure. Your 12-foot-wide driveway might be 12.25 feet in spots.
What stays in the truck. The drum doesn’t empty completely. You’re paying for concrete that never leaves the truck.
Thicker edges. Where the slab meets an existing surface or the ground drops away, you’ll use more than the calculated volume.

Running short on a driveway pour is a disaster. The ready-mix plant might not have another truck available for hours. Cold joints (where fresh concrete meets partially cured concrete) create a permanent weak line across your driveway. The extra 10% costs maybe $100-$150 in material. Fixing a cold joint costs thousands.

Sub-Base Prep: The Hidden Cost Most People Miss

Your driveway is only as good as what’s underneath it. A properly prepared sub-base is critical, and it adds cost that isn’t part of your concrete calculation.

Standard Sub-Base

4-6 inches of compacted gravel (crushed rock, not round stone)
Cost: $1.50-$3.00 per square foot for material and compaction
For our example (480 SF): $720-$1,440

What a Good Sub-Base Prevents

Settling and cracking from soft spots
Water erosion underneath the slab
Frost heaving in cold climates
Uneven curing from inconsistent moisture

When You Need More

If your soil is clay, organic (dark, soft dirt), or has been recently filled or disturbed, you may need:

Geotextile fabric under the gravel ($0.15-$0.30/SF)
Deeper gravel base (8-12 inches)
Soil compaction testing ($200-$500)

I’ve seen driveways crack within a year because the homeowner skipped proper base prep to save money. The concrete itself was fine. The ground underneath failed. Don’t make this mistake.

Quick Reference Table: Driveway Concrete Volume

Here are pre-calculated volumes for common driveway sizes. All figures include the 10% waste factor.

Driveway Size	4” Thick (yards)	5” Thick (yards)	6” Thick (yards)
10 x 20 (200 SF)	2.7	3.4	4.1
12 x 30 (360 SF)	4.9	6.1	7.3
12 x 40 (480 SF)	6.5	8.2	9.8
12 x 50 (600 SF)	8.1	10.2	12.2
20 x 30 (600 SF)	8.1	10.2	12.2
20 x 40 (800 SF)	10.9	13.6	16.3
24 x 40 (960 SF)	13.0	16.3	19.6
24 x 50 (1,200 SF)	16.3	20.4	24.4

Double-check your numbers: Plug your exact dimensions into the concrete calculator for a precise volume, especially if your driveway has irregular shapes or multiple sections.

What About the Apron and Flare?

Most driveways have a flared section where they meet the street (the apron). This section is often wider and sometimes thicker than the main driveway, and it’s easy to forget when calculating volume.

Apron dimensions vary by municipality, but a typical residential apron is:

Width: 16-24 feet (wider than the driveway)
Depth: 5-10 feet (from the sidewalk to the street)
Thickness: Often 6 inches (required by many cities regardless of driveway thickness)

Calculate the apron separately and add it to your main driveway volume. On a project with a 12-foot-wide driveway and a 20-foot-wide apron that’s 8 feet deep at 6 inches thick, that apron alone adds another 3.3 cubic yards.

Cost Breakdown: What a Concrete Driveway Actually Runs

For our 12x40 driveway example at 5 inches thick (8.5 cubic yards):

Item	Cost
Concrete (8.5 yards x $140/yard)	$1,190
Gravel sub-base (480 SF)	$960-$1,440
Forming and stakes	$300-$500
Rebar (#4 on 18” centers)	$350-$500
Labor (pour, finish, cure)	$1,500-$2,500
Total installed	$4,300-$6,130

That works out to $9-$13 per square foot installed for a standard broom-finished driveway with rebar reinforcement. Stamped or colored concrete adds $4-$10 per square foot on top of that.

For a more detailed breakdown of concrete labor and material costs, see our guide on concrete patio cost per square foot. The per-unit pricing translates directly to driveways.

Common Driveway Concrete Mistakes

Ordering Bagged Concrete for a Driveway

A standard two-car driveway needs 15-20+ cubic yards of concrete. That’s over 1,000 bags of 60-pound mix. Even a small single-car driveway needs 200+ bags. Use ready-mix. Always.

Pouring Without Expansion Joints

Driveways need control joints (saw-cut or tooled) every 8-12 feet in both directions, plus expansion joints where the driveway meets the garage floor and sidewalk. Without them, the concrete decides where to crack, and it won’t be in a straight line.

Skipping Reinforcement

A driveway without rebar or at minimum wire mesh is asking for trouble. Vehicles create repetitive stress loads that unreinforced concrete can’t handle long-term.

Pouring Too Thin to Save Money

Going from 5 inches to 4 inches saves about 20% on concrete cost. It also cuts your slab’s load capacity by roughly 40%. That math doesn’t work in your favor.

Frequently Asked Questions

How many cubic yards of concrete do I need for a 2-car driveway?

A typical two-car driveway (24 feet wide by 40 feet long at 5 inches thick) needs about 16-17 cubic yards of concrete including 10% waste. That’s usually two full truckloads.

How thick should a concrete driveway be?

Five inches is the sweet spot for most residential driveways. Go to 6 inches if you have heavy vehicles (RVs, trailers), clay soil, or live in a freeze-thaw climate. Never go below 4 inches.

How much extra concrete should I order?

Always add 10% to your calculated volume. On larger pours (15+ yards), you can sometimes reduce this to 7-8%, but never skip it entirely. Running short mid-pour is the most expensive mistake you can make.

Can I pour a concrete driveway myself?

Technically, yes. Practically, a driveway pour is one of the hardest DIY concrete projects. You’re dealing with large volumes, tight timing (concrete starts setting the moment it’s mixed), and finishing a large area before it cures. Most DIY driveway pours I’ve seen have visible cold joints, uneven surfaces, or poor finishing. If the driveway is under 300 square feet and you have help, it’s doable. For anything larger, hire a crew.

How long before I can drive on new concrete?

Wait a minimum of 7 days for passenger vehicles. For heavier trucks or trailers, wait 14 days. Full cure takes 28 days. I know it’s tempting to use it sooner, but early loading causes surface damage and micro-cracking that shortens the slab’s life.

Get Your Numbers Right the First Time

The calculation itself is straightforward: length times width times thickness, convert to cubic yards, add 10%. The hard part is getting accurate measurements and choosing the right thickness for your situation.

Use our concrete calculator to run the math, then check the concrete cost per yard tool to price it out with your local rates. Get quotes from 2-3 local ready-mix suppliers. Prices vary more than you’d expect, even within the same city. And always, always order that extra 10%.

For a broader look at slab pricing including reinforcement options and decorative finishes, see our guide on concrete slab cost. And if you’re pricing concrete as part of a larger project, the how to calculate concrete for a patio guide covers irregular shapes and layout variations. The same core formulas used here apply to footings, posts, and walls as well. For a full walkthrough across all common pour types, see the contractor guide on how much concrete do I need.

Brad is a third-generation contractor with over 20 years in residential construction and concrete work. He founded EstimationPro.AI to help contractors and homeowners estimate projects accurately and confidently.