Single Bag Yield 0.6 cu ft
Bags per Cubic Yard 45 bags/yd³
Water per Bag 3 qts (2.8L)
Full Pallet Count 42 bags (3360 lbs)

Interactive 80 lb Concrete Bag Job Calculator

Calculate exact total bag counts, dry material weight, and water volume for your project dimensions.

ENGINEERING SCHEMATIC
Standard Ready-Mix Pre-Mixed Dry Bag Yields
80 LB 0.60 cu.ft 45 Bags = 1 yd³ 60 LB 0.45 cu.ft 60 Bags = 1 yd³ 50 LB 0.375 cu.ft 72 Bags = 1 yd³ 40 LB 0.30 cu.ft 90 Bags = 1 yd³
Calculation Input Mode
Example default values loaded
Quick Presets:
Project Concrete Requirements
Bagged Concrete Product & Published Yield

Important Technical Fact: Bag yield is product-specific. Bag weight alone does not determine concrete yield. An 80 lb standard gravel mix yields approximately 0.60 cu ft, whereas an 80 lb lightweight aggregate mix yields up to 1.00 cu ft. Always verify the yield printed on your bag's Technical Data Sheet (TDS).

Whole Bags to Buy
45 Bags

Primary whole-bag retail purchasing requirement (based on ceiling rounding without hidden waste).

Exact Fractional Requirement 45.00 bags Theoretical proportional requirement before whole-bag purchasing.
Purchased Packaged Dry Weight 3,600 lb (1.80 US tons | 1,633 kg) Total packaged dry weight to haul and transport from retailer.
Exact Fractional Dry-Mix Weight 3,600.0 lb (1.80 US tons | 1,632.9 kg) Net unmixed dry ingredient mass required for exact volume.
Net Project Volume 1.00 cu yd (27.0 cu ft | 0.76 m³) Exact geometric placement volume without job-site waste factor.

Product Specification: Concrete Mix (No. 1101)

Manufacturer: QUIKRETE | Published Nominal Yield: 0.6 cu_ft/bag | Document: QUIKRETE Technical Data Sheet No. 1101

Mathematical Derivation & Audit Steps

  1. Determine Project Concrete Volume

    Direct project volume provided by user input.

    Volume = User Specified Volume

    Substituted: 1 cu_yd

    Result: 1 cu_yd

  2. Normalize Project Volume to Canonical SI Base Units (m³)

    Convert specified volume to cubic meters using NIST international conversion standards.

    Volume (m³) = Volume × Conversion Factor

    Substituted: 1 cu_yd = 0.764554857984 m³

    Result: 0.764554857984 m³

  3. Normalize Published Product Yield to Canonical SI Base Units (m³/bag)

    Convert published yield per bag to canonical cubic meters based on manufacturer technical specifications.

    Yield (m³/bag) = Published Yield × Conversion Factor

    Substituted: 0.6 cu_ft = 0.0169901079552 m³/bag

    Result: 0.0169901079552 m³/bag (0.6 cu ft/bag)

  4. Divide Project Volume by Published Yield per Bag

    Divide canonical project volume by published canonical yield per bag to determine exact fractional bag requirement.

    Fractional Bags = Project Volume (m³) / Yield per Bag (m³)

    Substituted: 0.764554857984 m³ / 0.0169901079552 m³/bag = 45

    Result: 45 bags

  5. Calculate Whole Bags to Purchase (Ceiling)

    Round fractional bags up to the next integer because packaged dry concrete mix can only be purchased in whole bags at retail.

    Whole Bags = ceil(Fractional Bags)

    Substituted: ceil(45) = 45

    Result: 45 whole bags

  6. Calculate Exact Required Dry-Mix Weight (Fractional)

    Multiply fractional bag requirement by nominal dry bag weight to determine the proportional unmixed dry mix material requirement for the net geometric volume (note: this is a mathematical material requirement, not a retail packaging unit).

    Fractional Dry Weight = Fractional Bags × Bag Weight

    Substituted: 45 × 80 lb = 3600 lb

    Result: 3600 lb (1632.9325320000003 kg)

  7. Calculate Purchased Packaged Dry Weight (Whole Bags)

    Multiply whole bags to buy by nominal dry bag weight to determine the total physical packaged dry weight purchased at retail and transported from the supplier.

    Purchased Packaged Weight = Whole Bags × Bag Weight

    Substituted: 45 × 80 lb = 3600 lb

    Result: 3600 lb (1632.9325320000003 kg)

Slab Surface Area Coverage by Depth

How many square feet will 80 lb bags cover? The table below breaks down coverage for 1 bag, 10 bags, and a full pallet (42 bags) across standard slab depths:

Slab Thickness Coverage per 1 Bag Coverage for 10 Bags Coverage for Full Pallet (42 bags)
2″ Depth 3.6 sq ft 36 sq ft 151.2 sq ft
3″ Depth 2.4 sq ft 24 sq ft 100.8 sq ft
4″ Depth 1.8 sq ft 18 sq ft 75.6 sq ft
6″ Depth 1.2 sq ft 12 sq ft 50.4 sq ft
Coverage Rule: Concrete volume expands zero percent during curing. Always include a 10% safety buffer for uneven dirt subgrade when calculating bag counts.

Recommended Uses for 80 lb Concrete Bags

  • Contractor standard for all structural bagging: footings, slabs, walls
  • Most economical cost per cubic foot of mixed concrete
  • Thickened slab foundations, garage door aprons, and hot tub pads
  • High-volume manual site batching with electric or gas barrel mixers

80 lb Bags vs. Ready-Mix Truck Delivery

When does it make sense to buy bags versus ordering a ready-mix delivery truck?

Break-Even Threshold ~1.5 to 2.0 cu yds (68 to 90 bags)
Labor Intensity High (Manual Mixing) Requires barrel mixer or hoe & wheelbarrow
Risk of Cold Joints Moderate to High Must mix and pour fast enough to prevent layering
Short-Load Fee Penalty None for Bags Trucks charge $100–$250 extra on orders under 5 yd³

If your project requires more than 2 cubic yards, ready-mix truck delivery is almost always more economical and structurally superior. Check our Ready-Mix Truck Load Planner to compare transit costs.

Frequently Asked Questions: 80 lb Concrete Bag

How many 80 lb bags of concrete make a cubic yard?

It takes exactly undefined bags of 80 lb concrete to yield 1 cubic yard (27 cubic feet) of mixed concrete. When accounting for a standard 10% safety margin for ground unevenness and spillage, plan for undefined bags per cubic yard.

How much concrete does a 80 lb bag make?

One 80 lb bag yields approximately 0.6 cubic feet of wet concrete (equal to undefined cubic yards or undefined cubic meters) when mixed with 3 quarts (2.8 liters) of clean water per ASTM C387 specifications.

How many square feet does one 80 lb bag cover at 4 inches?

At a standard 4-inch slab thickness (0.333 ft), one 80 lb bag covers approximately 1.80 square feet. To pour a 10x10 slab (100 sq ft) at 4 inches depth, you would need 62 bags (including 10% extra).