Enter the volume you have or plan to order.Please enter a valid volume greater than 0.
Standard slab: 4 in. Driveway: 6 in. Topping: 2 in.
Please enter a valid thickness greater than 0.
Set to 0 to see theoretical coverage. Add 10% to account for uneven subgrade and spills.
$
For a material cost estimate. US average: $100–$150/yd³.
Results appear instantly. No sign-up required.
Your Coverage Estimate
Coverage Area (at entered thickness)
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Square Feet (ft²)
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Square Yards (yd²)
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Square Meters (m²)
Coverage per Bag (at same thickness)
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ft² / 40 lb bag
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ft² / 60 lb bag
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ft² / 80 lb bag
—Volume Input
—Volume (ft³)
—Thickness
—Waste Factor
Estimated Material Cost
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Concrete material cost only. Add labor, delivery ($100–$300), forming, and finishing for a full project budget. Use our Full Project Estimator for a complete breakdown.
Per-bag coverage: 40 lb = 0.30 ft³ | 60 lb = 0.45 ft³ | 80 lb = 0.60 ft³
ft² per bag = bag yield (ft³) ÷ Thickness (ft)
How to Use This Concrete Coverage Calculator
Know your volume.
Enter the concrete volume you have available or plan to order. Ready-mix is quoted in cubic yards by the supplier — use the cubic yards option. If you're working from a bag count, multiply bags by their yield (0.45 ft³ for 60 lb, 0.60 ft³ for 80 lb) and select cubic feet. If you already know the area you need to cover, use our Slab Calculator instead to work backwards.
Enter your intended pour thickness.
Use the quick-select buttons for the most common thicknesses — 2 in for toppings and resurfacing, 4 in for standard flatwork, 6 in for driveways. If you're pouring at a non-standard depth, type it directly. This is the single biggest variable: cutting thickness in half doubles coverage, cutting it to a third triples it.
Set the waste factor.
Leave it at 0% to see maximum theoretical coverage — useful for understanding how far a set volume can go under ideal conditions. Set it to 10% for a realistic working figure that accounts for uneven subgrade, form bow, and mixing losses. The calculator reduces your effective volume by the waste percentage before computing area.
Use the coverage area to plan your pour.
The square footage result tells you the maximum area your volume will cover at the specified depth. If it's less than your project area, you need more concrete — use the slab calculator to determine the volume gap. If it's more than you need, you can reduce your order, but never cut it so close that you risk running short mid-pour.
⚠ Pro Tip: Subgrade is never perfectly flat. Low spots — even just half an inch below nominal — consume a disproportionate amount of concrete because area is large but depth compounds quickly. On a 500 sq ft pour, a jobsite that's consistently half an inch low adds over 15 cubic feet of concrete you didn't plan for. Always check and correct your subgrade before forming, not after.
Concrete Coverage Formula
Concrete coverage is the inverse of the slab volume formula. Given a fixed volume, the area it covers is determined entirely by how thinly or thickly you spread it. The math is straightforward, but the unit conversions catch most people.
Step
Formula
Example (1 yd³, 4 in thick)
1. Convert volume to cubic feet
yd³ × 27
1 × 27 = 27 ft³
2. Convert thickness to feet
inches ÷ 12
4 ÷ 12 = 0.333 ft
3. Coverage in square feet
ft³ ÷ thickness (ft)
27 ÷ 0.333 = 81 ft²
4. Coverage in square yards
ft² ÷ 9
81 ÷ 9 = 9 yd²
5. Coverage in square meters
ft² × 0.092903
81 × 0.092903 = 7.52 m²
Coverage Reference Table — 1 Cubic Yard at Common Thicknesses
Square footage covered by 1 cubic yard of concrete at various pour thicknesses. No waste factor applied.
Thickness
Coverage (ft²)
Coverage (yd²)
Coverage (m²)
Typical Use
1 inch
324 ft²
36.0 yd²
30.1 m²
Thin topping, decorative overlay
1.5 inches
216 ft²
24.0 yd²
20.1 m²
Bonded topping slab minimum
2 inches
162 ft²
18.0 yd²
15.1 m²
Topping slab, resurfacing
3 inches
108 ft²
12.0 yd²
10.0 m²
Thin flatwork (light duty only)
4 inches
81 ft²
9.0 yd²
7.52 m²
Standard patio, walkway, shed pad
5 inches
64.8 ft²
7.2 yd²
6.02 m²
Light driveway, garage apron
6 inches
54 ft²
6.0 yd²
5.02 m²
Residential driveway, garage floor
8 inches
40.5 ft²
4.5 yd²
3.76 m²
Heavy vehicle pad, commercial
10 inches
32.4 ft²
3.6 yd²
3.01 m²
Structural slab (engineer required)
12 inches
27 ft²
3.0 yd²
2.51 m²
Structural/foundation (engineer required)
All values based on 1 cubic yard = 27 cubic feet. Add 10% to volume before calculating for real-world ordering.
How Thickness Affects Coverage — and Why It Matters More Than Volume
The most important insight from this calculator: thickness has a disproportionate impact on coverage. Halving your pour thickness exactly doubles your coverage area from the same volume of concrete. This makes thickness the primary lever to pull when you're trying to extend a fixed volume further — or when you're trying to understand why a pour came up short.
Coverage area (ft²) for common volumes and thicknesses — no waste factor. Verify with calculator above for your exact inputs.
Volume
2 in thick
4 in thick
6 in thick
8 in thick
0.5 yd³ (13.5 ft³)
81 ft²
40.5 ft²
27 ft²
20.3 ft²
1 yd³ (27 ft³)
162 ft²
81 ft²
54 ft²
40.5 ft²
2 yd³ (54 ft³)
324 ft²
162 ft²
108 ft²
81 ft²
3 yd³ (81 ft³)
486 ft²
243 ft²
162 ft²
121.5 ft²
5 yd³ (135 ft³)
810 ft²
405 ft²
270 ft²
202.5 ft²
10 yd³ (270 ft³)
1,620 ft²
810 ft²
540 ft²
405 ft²
1 ft³ (bag yield: 80 lb)
3.6 ft²
1.8 ft²
1.2 ft²
0.9 ft²
If your actual coverage fell short of what this calculator predicted, the most common culprit is inconsistent subgrade depth — not a bad batch of concrete. Pull the bottom of your forms level with a laser or string line before pouring; a few minutes of subgrade correction saves more concrete than any other jobsite action.
Common Mistakes When Using Concrete Coverage
⚠️
Treating the coverage number as exact.
The calculator gives you theoretical coverage — the maximum area assuming perfectly flat subgrade and zero losses. Real pours on real jobsites consistently come in 5–15% under theoretical because subgrade has undulations, forms aren't perfectly plumb, and mixing water affects yield. Never use 0% waste for actual procurement decisions.
📐
Calculating coverage and then reducing thickness to stretch the volume.
This is backwards logic that ends in structural failure. Thickness is specified by the application's load requirement — not by how much concrete you bought. Pouring a 3-inch slab where 4 inches was specified because you ordered short is how slabs crack. Order more concrete, not a thinner slab.
📦
Using the bag yield printed on the bag as a guaranteed number.
Bag yields (0.45 ft³ for 60 lb, 0.60 ft³ for 80 lb) are theoretical yields at the recommended water-to-cement ratio. Wet mixes with extra water have slightly more volume but weaker concrete; stiff mixes with less water yield slightly less. In practice, assume 5–8% less coverage per bag than the label suggests.
🔢
Confusing square footage with cubic footage when ordering.
Coverage area is in square feet. Ready-mix is ordered in cubic yards. These are completely different units and cannot be compared directly without thickness. A contractor who tells a supplier "I need 500 square feet worth" will get a confused response — you need to specify volume. Use this calculator to get the area, then use the slab calculator to get the cubic yards to order.
🧱
Applying slab coverage math to topping slabs without checking bond requirements.
Self-leveling concrete and bonded toppings have different effective yield characteristics than standard concrete. SLC products in particular have manufacturer-specified coverage rates that account for their flow properties and typical application thickness. Always check the product data sheet — this calculator's formula applies to standard concrete mixes only.
Frequently Asked Questions
One cubic yard (27 cubic feet) of concrete covers 81 square feet at 4 inches thick, 54 square feet at 6 inches thick, and 40.5 square feet at 8 inches thick. The formula is: sq ft = (yd³ × 27) ÷ thickness in feet. Double the thickness and you halve the coverage — it's a direct inverse relationship.
An 80 lb bag of concrete yields 0.60 cubic feet. At 2 inches thick it covers 3.6 square feet; at 4 inches thick, 1.8 square feet; at 6 inches thick, 1.2 square feet. For any other thickness, divide 0.60 by the thickness expressed in feet. In practice, expect 5–8% less due to mixing losses and subgrade variation.
A 60 lb bag yields 0.45 cubic feet. At 2 inches thick it covers 2.7 square feet; at 4 inches thick, 1.35 square feet; at 6 inches thick, 0.9 square feet. The 60 lb bag is 25% less yield than an 80 lb bag, so you'll need more bags to cover the same area at the same thickness.
Coverage (sq ft) = Volume (ft³) ÷ Thickness (ft). Convert your volume to cubic feet first — multiply cubic yards by 27 or cubic meters by 35.3147. Convert thickness to feet — divide inches by 12. Then divide volume by thickness. To get square yards, divide sq ft by 9. To get square meters, multiply sq ft by 0.092903.
At 4 inches (0.333 ft) thick over 100 square feet, you need 33.3 cubic feet of concrete. With 80 lb bags (0.60 ft³ each): 56 bags. With 60 lb bags (0.45 ft³ each): 74 bags. Always add 10% for waste — that's 62 bags of 80 lb or 82 bags of 60 lb for a job this size. At this scale (roughly 1.23 cubic yards), ready-mix delivery becomes worth pricing out — mixing 56+ bags by hand is exhausting and produces inconsistent results.
Three main reasons: uneven subgrade (low spots consume more concrete than your nominal pour depth), form bow (forms deflect outward under concrete pressure, increasing actual pour volume), and bag yield variability (actual yield per bag is often 5–8% below the label's theoretical figure). The 10% waste factor exists to bridge this gap. If you're consistently coming up more than 10% short, your subgrade preparation needs attention — low spots are almost always the culprit on pours over 200 square feet.
The math is the same — volume divided by thickness equals area — but self-leveling concrete (SLC) is rarely a standard concrete mix. Most SLC products have their own coverage specifications per bag or per unit at a given thickness, listed in the product data sheet. Use those manufacturer figures for procurement; they account for the product's specific yield characteristics. This calculator is accurate for standard portland cement-based concrete mixes and mortar mixes.
No. Concrete resurfacing products (like Quikrete Resurfacer or similar) are thin-bed materials applied at 1/8 to 1/4 inch typical thickness. They have manufacturer-specified coverage rates per bag, measured in square feet at a given depth. Applying the standard volumetric formula at those thicknesses will give you wildly optimistic numbers because the calculation assumes perfectly uniform depth across the entire surface — which is almost never true on an existing worn slab. Use the coverage printed on the product packaging for resurfacing jobs.
For standard concrete (not self-leveling or resurfacing products), the practical minimum for a structural pour is 2 inches for a bonded topping and 3.5 to 4 inches for any freestanding slab. Below 3.5 inches for a freestanding slab, the concrete lacks the cross-section to resist the tensile stresses from curing shrinkage and thermal movement, and it will crack within months. Any pour under 2 inches with standard concrete should be replaced with a purpose-engineered thin-set or repair mortar product.
Multiply cubic yards by 27 to get cubic feet, then divide by your pour thickness in feet. For example: 2 cubic yards × 27 = 54 cubic feet. At 6 inches thick (0.5 ft): 54 ÷ 0.5 = 108 square feet. At 4 inches thick (0.333 ft): 54 ÷ 0.333 = 162 square feet. Use the calculator above to handle all unit conversions automatically.
