How Many Bags of Concrete Do I Need? 40 vs 60 vs 80 lb Comparison

Quick Answer: Bags Per Cubic Yard

Here's what you need to know upfront:

• 40 lb bags: 90 bags per cubic yard
• 60 lb bags: 60 bags per cubic yard
• 80 lb bags: 45 bags per cubic yard

Most homeowners find 60 lb bags offer the best balance of coverage and handling weight.

Coverage Per Bag at 4 Inches Thick

For a standard 4-inch thick slab, here's what each bag covers:

• 40 lb bag: 0.30 square feet (roughly 6.5" x 6.5" area)
• 60 lb bag: 0.45 square feet (roughly 8" x 8" area)
• 80 lb bag: 0.60 square feet (roughly 9.5" x 9.5" area)

40 vs 60 vs 80 Pound Bags: Which to Choose?

40 Pound Bags

Best for: Small repairs, fence posts, setting mailbox posts

Pros:

• Easiest to carry and handle
• Good for overhead or awkward positions
• Less wasted if you only need a small amount

Cons:

• Most expensive per cubic foot
• Need many more bags for larger projects
• More bags to open and mix

60 Pound Bags (Most Popular)

Best for: Small to medium DIY projects, deck footings, small slabs

Pros:

• Good balance of weight and coverage
• Widely available everywhere
• Middle-ground pricing
• Manageable for most adults

Cons:

• Still heavy for some people
• Less efficient than 80 lb for large projects

80 Pound Bags

Best for: Larger projects where you want fewer bags to handle

Pros:

• Best price per cubic foot
• Fewer bags to open, mix, and dispose of
• Most efficient for volume

Cons:

• Heavy—lifting repeatedly is tiring
• Harder to mix thoroughly by hand
• Can be difficult to handle alone

Cost Comparison (Average Prices)

Prices vary by region and retailer, but here's a typical breakdown:

• 40 lb bag: $3.50-4.50 ($0.09-0.11 per lb)
• 60 lb bag: $4.50-5.50 ($0.08-0.09 per lb)
• 80 lb bag: $5.50-7.00 ($0.07-0.09 per lb)

Per cubic yard cost:

• 40 lb bags: $315-$405 (90 bags)
• 60 lb bags: $270-$330 (60 bags)
• 80 lb bags: $247-$315 (45 bags)

The 80 lb bags save roughly 15-20% compared to 40 lb bags for the same volume.

When to Use Bagged Concrete vs. Ready-Mix

Use Bagged Concrete When:

• Project needs less than 1 cubic yard
• You're doing the work alone or with limited help
• No truck access to pour location
• Working in small batches over several days
• Setting posts (fence, deck, mailbox)
• Small repairs and patches

Use Ready-Mix (Truck Delivery) When:

• Project needs more than 1-2 cubic yards
• You have help to pour and finish quickly
• Truck can access pour location
• Large slabs (driveways, patios, garage floors)
• Time is critical—need to pour fast

The Break-Even Point

Ready-mix concrete typically costs $125-150 per cubic yard delivered (varies by location). When you factor in your time mixing bags, ready-mix usually makes more sense for anything over 1 cubic yard. For a typical 10x10 foot patio at 4 inches thick, you're right at the break-even point—either option works.

Mixing Tips for Bagged Concrete

• Don't add too much water: Follow package directions exactly. Soupy concrete is weak concrete.
• Mix thoroughly: Unmixed dry pockets create weak spots
• Work in small batches: Only mix what you can use in 15-20 minutes
• Rent a mixer: For more than 10 bags, a rental mixer saves your back and ensures better mixing

Calculate Your Exact Needs

Don't guess—use our concrete calculator to get the exact number of bags for your project. Enter your dimensions, select your bag size, and get precise counts with cost estimates.