Easily Calculate How Many 60lb Bags Of Concrete Make A Yard

How many 60lb bags of concrete make a yard? You usually need about 75 to 76 bags of 60-pound concrete mix to make one cubic yard concrete. This number can change slightly based on the specific brand and how you mix it. Knowing this helps you buy the right amount for your project.

What a Cubic Yard Is

Think of a cubic yard as a big box. This box is 3 feet wide, 3 feet long, and 3 feet tall.
It is a standard way to measure bulk materials.
Materials like dirt, gravel, sand, or concrete are often measured in cubic yards.
Knowing this size is the first step.
You need to fill this big box with mixed concrete.
Bagged concrete comes in small amounts.
You need many small bags to fill the big box.

Grasping Concrete Bag Yield

Each bag of dry concrete mix makes a certain amount of wet concrete. This is called the concrete bag yield.
Yield is usually measured in cubic feet per bag.
Bag sizes are often 60 pounds or 80 lb concrete bag.
A 60-pound bag of concrete mix makes about 0.45 cubic feet of wet concrete.
An 80-pound bag makes a bit more.
It usually makes about 0.6 cubic feet of wet concrete.
The yield is printed on the concrete bag.
Always check the bag details.
This is important for your calculations.

Why Yield Matters

Knowing the yield helps you figure out how much concrete you get.
You buy concrete by the bag.
But you need a specific volume of concrete for your project.
The project volume is often measured in cubic feet or cubic yards.
Yield connects the bag size to the volume you get.
It tells you how much one bag will cover or fill.
If you know the total cubic feet you need, you can divide.
You divide the total need by the yield of one bag.
This tells you how many bags to buy.
Getting the yield right saves you money.
It stops you from buying too much.
It also stops you from running out of concrete.

Figure Out Cubic Feet in a Yard

We know a cubic yard is a box 3 feet by 3 feet by 3 feet.
To find the volume in cubic feet, you multiply the sides.
Volume = Length x Width x Height.
Volume = 3 feet x 3 feet x 3 feet.
Volume = 9 square feet x 3 feet.
Volume = 27 cubic feet.
So, one cubic yard is equal to 27 cubic feet.
This number is fixed. It does not change.
This is a key number for your calculation.
You want to fill 27 cubic feet of space.
You will use bags that each make about 0.45 cubic feet.

Calculating the Bags Needed

Now we can do the math.
You need 27 cubic feet of mixed concrete.
A 60-pound bag makes about 0.45 cubic feet.
To find the number of bags, you divide the total volume needed by the yield per bag.
Number of bags = Total cubic feet needed / Yield per bag.
Number of bags = 27 cubic feet / 0.45 cubic feet per bag.
Let’s do the division.
27 / 0.45 = 60.
Wait, this simple math gives 60.
But earlier we said 75 to 76 bags.
Why the difference?
The 0.45 cubic feet yield is an average.
It can change.
The amount of water you add changes the final volume a little.
Also, some concrete is lost.
It sticks to the mixer.
It spills.
It is not perfect in practice.
So, concrete companies often state a slightly lower yield for planning.
A more common yield used for a 60-pound bag is closer to 0.36 to 0.4 cubic feet.
Let’s use a yield of 0.36 cubic feet per 60lb bag.
Number of bags = 27 cubic feet / 0.36 cubic feet per bag.
27 / 0.36 = 75.
Let’s use a yield of 0.355 cubic feet per 60lb bag.
27 / 0.355 = about 76.
This is why the number is around 75 or 76 bags.
It depends on the exact yield assumption.
Most sources and professionals use 75 to 76 bags as a good estimate.
Always check the specific bag you buy.
The yield might be listed there.
Use the number on the bag if you can.
If not, assume 75-76 bags per cubic yard for a 60lb bag.

Putting It Together: Step-by-Step Calculation

Let’s lay out the steps clearly.
This helps you calculate concrete needed for any project size.

Step 1: Find the Project Volume in Cubic Feet

First, measure your project area.
You need the length, width, and thickness.
Use the same unit for all measurements.
Feet are easy for this.
Length in feet.
Width in feet.
Thickness in feet.
Thickness is often given in inches.
You need to change inches to feet.
There are 12 inches in 1 foot.
To change inches to feet, divide the inches by 12.
Example: A slab is 4 inches thick.
4 inches / 12 inches per foot = 0.333 feet.
Multiply length x width x thickness (in feet) to get total cubic feet.
Volume (cubic feet) = Length (ft) x Width (ft) x Thickness (ft).

Step 2: Check the Concrete Bag Yield

Look at the bag you plan to use.
Find the yield in cubic feet per bag.
For a 60-pound bag, this is often listed as around 0.45 cubic feet.
But for calculation purposes, expecting 0.36 cubic feet is safer to avoid coming up short.
Let’s assume 0.36 cubic feet for a 60lb bag for calculation.

Step 3: Calculate Number of Bags

Divide the total cubic feet needed by the yield of one bag.
Number of Bags = Total Cubic Feet / Yield per Bag (in cubic feet).

Example Calculation

Suppose you need a concrete slab.
It is 10 feet long.
It is 10 feet wide.
It is 4 inches thick.

Step 1: Find Volume in Cubic Feet.
Length = 10 ft.
Width = 10 ft.
Thickness = 4 inches. Change to feet: 4 / 12 = 0.333 ft.
Volume = 10 ft x 10 ft x 0.333 ft.
Volume = 100 square feet x 0.333 ft.
Volume = 33.3 cubic feet.

Step 2: Use Bag Yield.
We use 0.36 cubic feet per 60lb bag for planning.

Step 3: Calculate Bags.
Number of Bags = 33.3 cubic feet / 0.36 cubic feet per bag.
Number of Bags = about 92.5 bags.
You cannot buy half a bag.
Always round up to the next whole bag.
You need 93 bags.
It is also smart to buy a few extra bags.
This covers spills or small errors.
Maybe buy 95 or 96 bags for this project.

Comparing 60lb Bags and 80lb Bags

People often use 80 lb concrete bag sizes too.
How do they compare?
An 80-pound bag is heavier.
It makes more concrete per bag.
A common yield for an 80-pound bag is about 0.6 cubic feet.
Let’s use a slightly lower, safer yield for calculation, say 0.45 cubic feet per 80lb bag.
This lower yield accounts for real-world use.

Bags Per Cubic Yard (80lb Bag)

A cubic yard is 27 cubic feet.
Yield per 80lb bag = 0.45 cubic feet (using a conservative estimate).
Number of 80lb bags per cubic yard = 27 cubic feet / 0.45 cubic feet per bag.
27 / 0.45 = 60 bags.
So, you need fewer 80lb bags than 60lb bags for the same volume.
About 60 bags of 80lb mix make a cubic yard.
Remember, for 60lb bags, it was about 75-76 bags.

Cost of Concrete Bags

The cost of concrete bags varies.
Larger bags usually cost more per bag.
But they might be cheaper per cubic foot of concrete made.
Let’s imagine some prices:
60lb bag costs $5.
80lb bag costs $6.
Cost per cubic foot for 60lb bag (using 0.36 cf yield): $5 / 0.36 cf = $13.89 per cubic foot.
Cost per cubic foot for 80lb bag (using 0.45 cf yield): $6 / 0.45 cf = $13.33 per cubic foot.
In this example, the 80lb bag is slightly cheaper per cubic foot of mixed concrete.
This is often true.
Buying larger bags can save money on big jobs.
But 80lb bags are heavier to carry and mix.
Consider your strength and equipment.

Table: Bag Comparison

Bag Size	Approx. Yield (Cubic Feet)*	Approx. Bags per Cubic Yard*
60 lb	0.36	75
80 lb	0.45	60
*Using conservative yields for planning purposes. Actual yield may vary.

Concrete Coverage Area Based on Thickness

Knowing the bag yield helps figure out how much area a bag covers.
This depends on the concrete slab thickness.
Let’s use our planning yield of 0.36 cubic feet per 60lb bag.
Area = Volume / Thickness.

Coverage Examples (60lb bag, 0.36 cf yield)

1 inch thick (0.083 feet):
Area = 0.36 cubic feet / 0.083 feet = about 4.3 square feet.
A 60lb bag covers about 4.3 sq ft at 1 inch thick.
2 inches thick (0.167 feet):
Area = 0.36 cubic feet / 0.167 feet = about 2.15 square feet.
A 60lb bag covers about 2.15 sq ft at 2 inches thick.
3 inches thick (0.25 feet):
Area = 0.36 cubic feet / 0.25 feet = about 1.44 square feet.
A 60lb bag covers about 1.44 sq ft at 3 inches thick.
4 inches thick (0.333 feet):
Area = 0.36 cubic feet / 0.333 feet = about 1.08 square feet.
A 60lb bag covers about 1.08 sq ft at 4 inches thick.
6 inches thick (0.5 feet):
Area = 0.36 cubic feet / 0.5 feet = about 0.72 square feet.
A 60lb bag covers about 0.72 sq ft at 6 inches thick.

As the thickness increases, the area a single bag covers goes down.
This table helps quickly estimate bags for small areas.

Table: 60lb Bag Coverage

Thickness (Inches)	Thickness (Feet)	Approx. Coverage per 60lb Bag (Sq Ft)*
1	0.083	4.3
2	0.167	2.15
3	0.25	1.44
4	0.333	1.08
6	0.5	0.72
*Using a planning yield of 0.36 cubic feet per 60lb bag.

Figuring Out Total Concrete Needed for Projects

You need the total volume for your project in cubic feet.
This is the most important step to calculate concrete needed.
We already saw how to do this for a slab.
Length x Width x Thickness (all in feet).

Projects Other Than Slabs

Footings: These are long and often rectangular or square in shape.
Measure the length, width, and depth (thickness) of the footing trench.
Volume = Length x Width x Depth.
Do this for each section of footing. Add up the volumes.
Columns or Piers: These are often round or square.
For square: Side x Side x Height.
For round: Pi (3.14159) x Radius x Radius x Height. (Radius is half the diameter).
Steps: Steps have different shapes. Break them down into simple boxes.
Calculate the volume of each box section. Add them up.

Always measure carefully.
Double-check your measurements.
Using a consistent unit (like feet) is key.
Change inches to feet by dividing by 12.
Change centimeters to feet by dividing by 30.48.
Change meters to feet by multiplying by 3.28084.

Using a Concrete Volume Calculator

Math can be tricky.
Especially with different units.
A concrete volume calculator is a helpful tool.
You can find these online.
You enter the shape of your project (slab, footing, etc.).
You enter the measurements (length, width, thickness).
You choose the unit (feet, inches, meters).
The calculator tells you the total volume.
It usually tells you in cubic feet and cubic yards.
Some calculators even ask which bag size you will use (60lb or 80lb).
They then tell you how many bags you need.
Make sure the calculator uses a conservative yield number.
Or it might give you too few bags.
Using a calculator is fast and reduces math errors.
But it is good to know how to do it yourself too.
This helps you check the calculator’s answer.

Factors Changing Bag Count

We calculated around 75-76 bags per cubic yard for 60lb bags.
But the real number on site might be different.
Several things can change it:

Actual Bag Yield Variation

The yield printed on the bag is a guideline.
It can vary slightly from batch to batch.
How much water you add also affects the final volume.
Adding too much water makes weaker concrete.
It can also slightly increase the volume, but this is not a good practice.
Adding too little water makes it hard to mix and place.
Use the amount of water recommended on the bag.

Waste and Spillage

Concrete spills during mixing concrete bags.
Some mix stays in the wheelbarrow.
Some sticks to the mixing tool or mixer.
Some spills when pouring.
This waste means you need slightly more concrete than the calculated volume.
It is wise to add 5-10% extra bags for waste.
For a cubic yard needing 76 bags, 5% extra is about 4 bags (76 * 0.05 = 3.8).
So, buy 80 bags.
For large jobs, plan for more waste.

Uneven Subgrade or Thickness

The ground under your slab might not be perfectly flat.
If there are low spots, you fill them with concrete.
This makes the slab thicker in those areas.
A thicker slab uses more concrete volume.
Always prepare the ground well.
Make it level.
Set up forms carefully to keep the thickness correct.
Even with care, thickness can vary.
This is another reason to buy extra bags.

Mixing Concrete Bags Correctly

Mixing concrete bags is important for strength and yield.
Follow the instructions on the bag.
They tell you how much water to add.
Use clean water.
Add the dry mix to the water, not water to the mix.
Mix until it is uniform.
There should be no dry pockets left.
The mix should not be too wet or too dry.
Too wet makes weak concrete.
Too dry is hard to work with.
Using the right amount of water gives the expected yield.
It also makes strong, durable concrete.
Mix in a wheelbarrow or a concrete mixer.
A mixer is better for many bags.
Mix only what you can use in about 30-60 minutes.
Concrete starts to harden once mixed.

Cost Considerations When Buying Bags

The cost of concrete bags adds up.
Especially for large projects.
Calculate the total cost before you start.
Multiply the number of bags needed by the cost per bag.
Number of bags x Cost per bag = Total material cost.
Remember to include the cost of extra bags for waste.
Compare the cost of 60lb bags vs 80lb bags.
Compare the cost of bagged concrete vs ready-mix concrete.
For projects over 1-2 cubic yards, ready-mix might be cheaper and easier.
One cubic yard of ready-mix concrete is often delivered by a truck.
It costs maybe $100 to $150 per cubic yard plus delivery.
76 bags of 60lb concrete at $5 each is $380.
60 bags of 80lb concrete at $6 each is $360.
Bagged concrete costs more per cubic yard than ready-mix concrete.
But you can buy just what you need.
You mix it yourself.
This is good for small jobs.
Or jobs in hard-to-reach spots where a truck cannot go.

Reviewing Concrete Coverage Area Needs

Understanding concrete coverage area helps visualize the project.
A 10×10 foot slab is 100 square feet.
If it is 4 inches thick (0.333 feet), the volume is 33.3 cubic feet.
We figured this needs about 93 bags (60lb).
Think of 93 bags lined up. That’s a lot of bags!
Knowing the area helps confirm your volume calculation makes sense.
If you calculate a very small volume for a large area, something is wrong.
Always double check your measurements and math.
Use our table or calculate coverage per bag for your planned thickness.
Divide your total project area by the coverage per bag.
This gives another way to estimate bags.

Example: 100 sq ft area, 4 inches thick.
Coverage per 60lb bag at 4 inches thick is about 1.08 sq ft.
Number of bags = Total Area / Coverage per bag.
Number of bags = 100 sq ft / 1.08 sq ft per bag.
Number of bags = about 92.6 bags.
Round up to 93 bags. This matches our volume calculation.
Both methods should give similar results.

Calculating for Specific Concrete Slab Thicknesses

Let’s look at common concrete slab thickness values.
And how many 60lb bags (using 0.36 cf yield) are needed per square foot.

2 inches thick (0.167 ft):
Bags per sq ft = 0.167 cubic feet needed per sq ft / 0.36 cubic feet per bag.
Bags per sq ft = about 0.46 bags.
For a 100 sq ft area: 100 sq ft * 0.46 bags/sq ft = 46 bags.
3 inches thick (0.25 ft):
Bags per sq ft = 0.25 cubic feet needed per sq ft / 0.36 cubic feet per bag.
Bags per sq ft = about 0.69 bags.
For a 100 sq ft area: 100 sq ft * 0.69 bags/sq ft = 69 bags.
4 inches thick (0.333 ft):
Bags per sq ft = 0.333 cubic feet needed per sq ft / 0.36 cubic feet per bag.
Bags per sq ft = about 0.925 bags.
For a 100 sq ft area: 100 sq ft * 0.925 bags/sq ft = 92.5 bags. Round up to 93.
5 inches thick (0.417 ft):
Bags per sq ft = 0.417 cubic feet needed per sq ft / 0.36 cubic feet per bag.
Bags per sq ft = about 1.16 bags.
For a 100 sq ft area: 100 sq ft * 1.16 bags/sq ft = 116 bags.
6 inches thick (0.5 ft):
Bags per sq ft = 0.5 cubic feet needed per sq ft / 0.36 cubic feet per bag.
Bags per sq ft = about 1.39 bags.
For a 100 sq ft area: 100 sq ft * 1.39 bags/sq ft = 139 bags.

This shows how fast the bag count grows with thickness.
A 6-inch slab needs over 50% more bags than a 4-inch slab of the same area.
Plan your thickness carefully.
This impacts cost a lot.

Table: Bags Per 100 Sq Ft (60lb Bag)

Thickness (Inches)	Approx. Bags per 100 Sq Ft (60lb)*
2	46
3	69
4	93
5	116
6	139
*Using a planning yield of 0.36 cubic feet per 60lb bag and rounding up total bags. Does not include extra for waste. Add 5-10% for safety.

Final Checks and Tips

Always measure your project site carefully.
Use feet for all measurements when calculating volume.
Change inches to feet (divide by 12).
Check the bag for its exact yield if possible.
Use a conservative yield number (like 0.36 cf for 60lb) for planning. This helps prevent running short.
Calculate total cubic feet needed.
Divide total cubic feet by the bag yield (in cubic feet).
Round the number of bags up to the next whole number.
Add 5-10% extra bags for waste, spills, and unevenness.
Consider using a concrete volume calculator to double-check your math.
Think about the cost of concrete bags. Compare 60lb and 80lb sizes.
For big jobs, compare bagged concrete cost to ready-mix cost.
Properly mixing concrete bags affects the yield and strength.
Know the concrete coverage area for a bag at your thickness to quickly estimate.
Pay attention to the planned concrete slab thickness. It greatly impacts the number of bags.

Calculating how many 60lb bags make a yard, or any other volume, is a few simple steps.
Find the total volume needed in cubic feet.
Know the yield of your bag in cubic feet.
Divide total volume by yield per bag.
Add extra bags for safety.
This makes sure you have enough concrete to finish your job right.

Frequently Asked Questions (FAQ)

Q: How many cubic feet are in a cubic yard?

A: There are 27 cubic feet in one cubic yard. This is always true.

Q: What is the typical yield of a 60lb concrete bag?

A: A 60lb bag typically yields about 0.45 cubic feet of concrete when mixed. However, for planning and to avoid being short, it’s safer to use a lower number like 0.36 cubic feet per bag.

Q: How many 60lb bags do I need for one cubic yard?

A: Using a planning yield of 0.36 cubic feet per bag, you would need 27 cubic feet / 0.36 cubic feet/bag = 75 bags for one cubic yard. Many sources say 75-76 bags is a good estimate.

Q: How many 80lb bags do I need for one cubic yard?

A: An 80lb bag usually yields about 0.6 cubic feet. Using a planning yield of 0.45 cubic feet per bag, you would need 27 cubic feet / 0.45 cubic feet/bag = 60 bags for one cubic yard. About 60 bags is a common estimate.

Q: How do I calculate the volume of a concrete slab?

A: Measure the length, width, and thickness of the slab area. Make sure all measurements are in feet. Multiply Length (ft) x Width (ft) x Thickness (ft) to get the volume in cubic feet. Remember to change inches to feet by dividing by 12.

Q: Why should I buy extra bags of concrete?

A: You should buy extra bags to account for waste from spills, concrete sticking to tools, and variations in the thickness of your slab or project area. Adding 5-10% extra bags is a good practice.

Q: Is it cheaper to use 60lb or 80lb concrete bags?

A: Often, the 80lb bags are slightly cheaper per cubic foot of mixed concrete. You need fewer bags overall with the 80lb size. However, they are heavier to carry and mix, which can be a factor for DIYers.

Q: How much area does a 60lb bag cover?

A: The area a 60lb bag covers depends on the thickness. Using a yield of 0.36 cubic feet, it covers about 4.3 sq ft at 1 inch thick, 1.08 sq ft at 4 inches thick, and 0.72 sq ft at 6 inches thick.

Q: Can I add more water to get more volume from a bag?

A: No, you should follow the water amount on the bag. Adding too much water makes the concrete weaker and less durable. It can slightly increase volume, but at the cost of strength.

Q: When should I use bagged concrete instead of ready-mix?

A: Bagged concrete is good for small jobs where you only need a few bags. It’s also useful for projects in areas a concrete truck cannot reach. For larger projects (over 1-2 cubic yards), ready-mix concrete is usually more cost-effective and easier to manage.