Estimate how many bags of QUIKRETE® Concrete Mix you need before buying material. Calculate a slab, rectangular footing, round post holes or a known concrete volume, then compare 40 lb, 50 lb, 60 lb, 80 lb and regional 90 lb bag sizes using the approximate yields published for QUIKRETE Concrete Mix No. 1101. Add an optional waste allowance, bag price and custom yield when your exact product is different.
Enter the finished concrete dimensions, choose the bag size, and the calculator will round up to the next whole bag. The built-in yields are for QUIKRETE Concrete Mix No. 1101; use Custom Yield for another product.
Your bag quantity will appear after you press Calculate Quikrete Bags.
Bag count is rounded up to whole bags. Verify the exact product yield and availability before buying.
The published approximate yield increases with bag weight. The calculator divides your required concrete volume by the selected yield and always rounds up to the next whole bag.
The calculator keeps geometry, yield, bag count and budget separate so you can see exactly how the estimate is produced.
Calculate the actual geometric volume before any allowance is added.
Add your own percentage for uneven forms, excavation differences or practical contingency.
Divide volume by bag yield and always round up because partial unopened bags are not purchase units.
Enter the actual store price per bag to build a simple material-only estimate.
Save the project shape, bag size, volume and estimated material cost for reference.
The blurred zero is only a placeholder. Typed measurements stay clear and never inherit a leading zero.
A Quikrete Bags Calculator answers a simple purchasing question: once you know the volume of concrete required, how many packaged bags will produce that volume? The calculation has two parts. First, measure the concrete shape and convert it to cubic feet. Second, divide that required cubic-foot volume by the approximate yield of the bag size you plan to buy. Because concrete mix is sold in complete bags, the final number is rounded up to the next whole bag.
The bag yield matters just as much as the project dimensions. QUIKRETE Concrete Mix No. 1101 is sold in several bag weights, and the company's current technical data sheet publishes a different approximate yield for each size. That is why this calculator does not use one universal “bags per cubic foot” number. A 40 lb bag is not treated like an 80 lb bag, and an 80 lb bag is not treated like a regional 90 lb bag.
According to the current QUIKRETE Concrete Mix No. 1101 data sheet, the listed approximate yields are 0.30 ft³ for a 40 lb bag, 0.375 ft³ for a 50 lb bag, 0.45 ft³ for a 60 lb bag, 0.60 ft³ for an 80 lb bag and 0.675 ft³ for a 90 lb bag. The same data sheet identifies the 90 lb size as regionally available. These are the exact built-in values used by the calculator.
| Bag Size | Approx. Yield | Approx. Litres | Bags Per 1 ft³ | Availability Note |
|---|---|---|---|---|
| 40 lb | 0.30 ft³ | 8.5 L | 3.34 | Listed Size |
| 50 lb | 0.375 ft³ | 10.6 L | 2.67 | Listed Size |
| 60 lb | 0.45 ft³ | 12.7 L | 2.23 | Listed Size |
| 80 lb | 0.60 ft³ | 17 L | 1.67 | Listed Size |
| 90 lb | 0.675 ft³ | 19.1 L | 1.49 | Regional Availability |
Whole Bags = Required Volume (ft³) ÷ Yield Per Bag (ft³) → Round Up
Suppose a project requires 6 ft³ of mixed concrete and you choose the 80 lb size. The published approximate yield is 0.60 ft³ per bag. Dividing 6 by 0.60 gives 10 bags. If the calculated result were 10.1 bags instead, you would need to round up to 11 complete bags before adding any separate spare-bag decision.
For a rectangular slab or pad, multiply length in feet by width in feet by thickness in feet. Because slab thickness is often measured in inches, divide the thickness by 12 before multiplying. A slab measuring 8 ft by 6 ft and 4 in thick has a geometric volume of 8 × 6 × (4 ÷ 12) = 16 ft³.
At 16 ft³, the bag count changes with the selected package. Using 80 lb Concrete Mix at approximately 0.60 ft³ per bag gives 26.67 bags, so the purchase quantity rounds to 27 bags before any added contingency. Using 60 lb bags at approximately 0.45 ft³ per bag gives 35.56, which rounds to 36 bags. The concrete volume is the same; only the packaging and handling unit changes.
A straight rectangular footing uses the same volume principle. Convert width and depth from inches to feet, then multiply them by the footing length in feet. If there are several identical footings, multiply the volume by the quantity. This page does not determine the structurally required footing dimensions. It only converts the dimensions you already have into a material estimate.
For dedicated footing shapes and metric/ready-mix planning, use the Concrete Footing Calculator. If the calculated footing volume is large, compare packaged mixing with ready-mix delivery rather than assuming bags are automatically the most practical option.
A round post hole is a cylinder. Convert the diameter to a radius, calculate π × radius² × depth, then multiply by the number of holes. The post itself occupies some of the hole, so the calculator offers a simple optional displacement percentage. For a precise estimate, calculate the actual post cross-sectional volume instead of relying on a generic percentage.
QUIKRETE also sells Fast-Setting Concrete Mix for setting posts. Its product page describes it as a special fast-setting blend intended for uses including fence, mailbox, basketball, deck and lamp posts. That product is not automatically assigned the No. 1101 Concrete Mix yield in this tool. When using a different product, select Custom Product / Yield and enter the current yield from that product's technical data sheet.
“QUIKRETE” is a brand covering many different concrete, mortar, repair, stucco and specialty products. A bag's weight alone does not guarantee the same finished volume as a different formulation. The official QUIKRETE calculator itself directs users to product Spec Data sheets for quantity and coverage information. For that reason, this page only hard-codes the published yields for Concrete Mix No. 1101.
If you are buying Fast-Setting Concrete, Crack Resistant Concrete Mix, QUIKRETE 5000, FastSet products, mortar, sand/topping mix or another packaged material, use the product-specific data rather than forcing the standard Concrete Mix yield into the estimate. This keeps the calculator useful without pretending all products perform identically.
A perfect mathematical volume assumes the form or excavation matches the planned dimensions exactly. Real projects can have uneven subgrade, over-excavation, rough post holes, slight form movement or small spills. QUIKRETE's own calculator notes that its yields are approximate and do not include uneven substrate or waste. This calculator therefore lets you enter your own allowance rather than automatically adding a fixed percentage.
A carefully formed small pad may need little contingency. A group of rough augered holes or an irregular repair can be harder to predict. Measure the actual work as late as practical, then decide how much extra material is sensible. The optional “Extra Spare Bags” field is separate from percentage waste so you can distinguish geometric contingency from simply keeping one or two unopened bags available.
Larger bags produce more concrete per bag, so they reduce the number of individual packages required. That does not automatically make the largest bag the best choice. Handling weight, lifting limits, transport, mixer capacity, store inventory and the number of people working on the pour can matter. A smaller bag may be easier to handle even though more bags are required.
The 80 lb size is a common reference point because its published approximate yield is 0.60 ft³, but the calculator supports all No. 1101 sizes listed in the technical data sheet. The 90 lb size is marked regional because QUIKRETE identifies its availability that way. Confirm what your local retailer actually stocks before planning the project around a particular size.
Do not estimate finished concrete volume from the amount of water added. The No. 1101 technical data sheet lists separate mixing-water guidance by bag size and explains that water is adjusted to obtain a workable mix. Yield is the approximate finished volume of the properly mixed product; it is not simply bag weight plus water volume.
The technical data sheet also warns against leaving standing puddles and provides product-specific mixing guidance. Follow the current bag instructions and data sheet rather than increasing water merely to make mixing easier. Excessive or incorrect water can affect concrete performance and is outside the scope of a bag-count calculator.
Packaged concrete is especially convenient for small pads, isolated footings, steps, post holes, repairs and projects where a ready-mix truck is unnecessary or cannot conveniently access the site. The original QUIKRETE Concrete Mix product page lists general uses including sidewalks, floors, steps, patios and curbs, while the technical sheet includes footings, walkways, platforms, post footings and other applications.
As project volume rises, bag count, lifting, mixing time and labor increase quickly. A single cubic yard equals 27 ft³. At the No. 1101 approximate yield of 0.60 ft³ per 80 lb bag, one cubic yard corresponds to 45 bags before waste. That is about 3,600 lb of dry packaged material. For larger pours, comparing ready-mix logistics can be sensible even when the bag maths is straightforward.
| Example | Concrete Volume | Bag Size | Approx. Yield | Whole Bags Before Waste |
|---|---|---|---|---|
| Small Repair / Pad | 3.0 ft³ | 40 lb | 0.30 ft³ | 10 |
| Small Slab | 6.0 ft³ | 50 lb | 0.375 ft³ | 16 |
| Walkway Section | 9.0 ft³ | 60 lb | 0.45 ft³ | 20 |
| Pad / Footing Group | 12.0 ft³ | 80 lb | 0.60 ft³ | 20 |
| Regional 90 lb Example | 13.5 ft³ | 90 lb | 0.675 ft³ | 20 |
Every numeric field starts empty. The soft blurred zero is a placeholder only; it is not an actual value stored in the input. If you click Length and type 8, the calculator receives 8, not 08. If you type 4 into Thickness, it receives 4, not 04. Once you start entering a number, the text is sharp and fully readable.
Resetting the calculator clears the numeric inputs again instead of inserting real zeros. This prevents the leading-zero behavior that can happen when calculators use a pre-filled value of zero. The result panel is also hidden when an input changes so an old bag count is not mistaken for a new calculation.
Store prices can change by retailer, location, bag size and time, so the calculator does not hard-code a retail price. Enter the price shown by the store you plan to use. The calculator multiplies the final whole-bag purchase count—including any spare bags you deliberately add—by that price. Sales tax, delivery, pallet deposits, tools, mixer rental and other costs are not automatically included.
If you are comparing a larger packaged-concrete project with ready-mix, use the Concrete Cost Calculator or Total Concrete Cost Calculator to separate material quantity from broader project costs.
Knowing you need 20 bags does not tell you how to mix, place, finish or cure the concrete. The current QUIKRETE Concrete Mix data sheet contains mixing-water guidance, mechanical and hand-mixing instructions, slab placement guidance, finishing information and curing recommendations. Read the current technical data and safety data before use.
The same data sheet emphasizes that curing is important to strength and durability and describes moisture and temperature considerations. Those construction decisions are outside the calculator's scope. The tool only estimates how many bags correspond to the dimensions and approximate product yield you enter.
Answers to common questions about bag sizes, yields, slab volume, post holes, waste and packaged concrete.
The current QUIKRETE Concrete Mix No. 1101 technical data sheet lists an approximate yield of 0.60 ft³ for an 80 lb bag. Check the exact product data sheet because other QUIKRETE formulations can differ.
One cubic yard is 27 ft³. Dividing 27 by the approximate 0.60 ft³ yield gives 45 bags before any waste allowance.
The No. 1101 data sheet lists approximately 0.45 ft³ for a 60 lb bag.
The No. 1101 data sheet lists approximately 0.375 ft³ for a 50 lb bag.
The No. 1101 data sheet lists approximately 0.30 ft³ for a 40 lb bag.
The current No. 1101 technical data sheet lists a 90 lb bag with an approximate 0.675 ft³ yield and identifies that size as regionally available.
Yes, but select Custom Product / Yield and enter the current yield from the exact Fast-Setting product data sheet. Do not automatically use the No. 1101 Concrete Mix yield for a different product.
No. The waste field starts empty. Enter the allowance appropriate for your project; the calculator will not silently add a fixed percentage.
Concrete mix is purchased in whole bags. If the calculated requirement is 10.2 bags, buying 10 bags would provide less than the estimated volume, so the result rounds to 11.
Yes. Choose Round Post Holes, enter hole diameter, depth and quantity, and optionally apply a simple post-displacement reduction.
Yes. Choose Known Volume and select cubic yards. The calculator converts the value to cubic feet before dividing by the selected bag yield.
The blurred zero is only a placeholder showing where to type. It is not a real value. Your typed measurement appears clearly and does not get an unwanted leading zero.
No. This is an independent ConcreteCreek.com estimating tool. For official product information and the manufacturer's own calculator, use QUIKRETE's website and current technical data sheets.
Verify your exact product, bag size, yield, water requirement and instructions with the current manufacturer information before buying or mixing.
Official product page listing 40, 50, 60 and 80 lb sizes and general uses.
View Product PageOfficial bag-size yields, mixing guidance, technical data, placement and curing information.
Open Data SheetManufacturer bag calculator covering concrete mixes, mortar, fast-setting concrete and other products.
Visit Official CalculatorFind current technical data and safety documents for different QUIKRETE products.
Browse Technical Data