Bagged Mix

Concrete Bag Calculator

Enter your project size and bag weight to get an exact bag count, total weight, and cost — works for Quikrete, Sakrete, or any bagged mix.

The Bag Calculator helps you figure out exactly how much material to buy before you order a truck or make a hardware store run. Enter your project size and bag weight to get an exact bag count, total weight, and cost — works for Quikrete, Sakrete, or any bagged mix. Instead of guessing at cubic yards or bag counts and hoping it's close, you enter the numbers you already have — the measurements from your plan, tape measure, or job site — and get a precise, ready-to-order figure back in seconds.

This tool is built for two kinds of people: contractors running a fast takeoff between jobs who need a number they can call into a supplier immediately, and homeowners or first-time DIYers who don't want to either overspend on wasted material or come up short mid-pour. Every calculator on ConcreteYard uses the same standard, industry-typical assumptions — 150 lb per cubic foot for normal-weight concrete, standard bag yields, and common mix ratios — so the numbers here should line up closely with what your supplier or hardware store confirms when you place the order.

Whether you're pricing out a job, planning a delivery, or just want to know how much to buy at the store today, this calculator gives you a number you can act on immediately — no spreadsheet, no account, and no guesswork required.

Project Dimensions

Bag yields: 40 lb ≈ 0.30 cu ft · 60 lb ≈ 0.45 cu ft · 80 lb ≈ 0.60 cu ft.

Calculated
Bag TicketCC-000000-000
Volume Needed0 cu ft
Yield per Bag0 cu ft
Total Weight0 lb
Est. Cost—
Bags to Buy0.00 yd³
Buy 1–2 extra bags beyond this count — short mixes are far more common than leftover bags on small pours.

How to Use the Bag Calculator

1. Measure accurately. Get exact dimensions in the units the calculator asks for — feet for length and width, inches for thickness are the most common setup. A rough guess in, a rough number out; precise measurements are what make this tool worth using over a mental estimate.

2. Enter your numbers. Fill in the fields above with your project's actual measurements. Default values are pre-filled as a sane starting point — replace every one of them with your real numbers before you rely on the result.

3. Adjust the settings. Where available, set your waste percentage, bag size, or price per yard to match your job. These small adjustments are what separate a rough ballpark from an order-ready figure.

4. Read the batch ticket. Click calculate and use the highlighted total as your order quantity — it already accounts for waste and rounds to a practical ordering increment where relevant.

Bag Yield Chart

Bag SizeYieldBags per yd³
40 lb0.30 cu ft~90
50 lb0.375 cu ft~72
60 lb0.45 cu ft~60
80 lb0.60 cu ft~45

When to Use Bags vs. Ready-Mix

Bagged concrete (Quikrete, Sakrete, and similar mixes) makes sense under roughly 1 cubic yard — fence posts, small pads, repairs. Past that, ready-mix delivery is almost always cheaper per yard and far less labor.

This calculator works for any bagged mix; yields are set by bag weight, not brand.

Frequently Asked Questions

How many 80 lb bags of concrete make a yard?

About 45 bags of 80 lb concrete mix make one cubic yard. A 60 lb bag needs about 60 bags per yard, and a 40 lb bag needs about 90.

How many bags of concrete do I need for fence posts?

Depends on the post hole size. A 10in diameter hole, 2 ft deep, takes roughly one 50lb bag. Switch to the Cylinder & Post Calculator for hole-specific figures.

How much water do I add per bag of concrete?

Most 60–80 lb bags call for roughly 3 quarts (about 2.8 L) of water per bag — always check your specific bag's instructions, as mixes vary.

Common Estimating Mistakes to Avoid

Skipping the waste factor. Uneven subgrade, formwork gaps, and simple spillage routinely eat 5–10% of your raw calculated volume. Ordering the exact math-perfect number is one of the most common ways to come up short mid-pour.

Rounding down instead of up. Ready-mix trucks deliver in fractions of a yard, but suppliers set order minimums. If your number lands at 4.1 yards, round to 4.25 or 4.5, not down to 4.

Mixing up units. Thickness is almost always in inches while length and width are in feet — plugging inches into a feet field (or vice versa) is the single most common calculator input error.

Treating irregular shapes as one rectangle. An L-shaped or curved area isn't one simple calculation. Break it into rectangles, run each section separately, and add the totals together for an accurate figure.

Tips for a Successful Pour

Order slightly more than the bare minimum — a short-load fee for a second truck almost always costs more than the extra material would have. Confirm your supplier's order minimum and short-load fee before you finalize a quantity that's close to the cutoff.

Check the weather. Concrete needs temperatures generally above 40°F to cure properly without special cold-weather additives, and pouring in direct heat or high wind can cause the surface to dry and crack before it has a chance to properly set.

Have everything staged before the truck arrives — forms set, base compacted, tools (screed board, bull float, edger) on site, and enough hands to place and finish the pour before it starts to set.

Plan your control joints in advance for any flatwork. Joints control where concrete cracks as it cures and shrinks — skipping them doesn't prevent cracking, it just makes the cracks unpredictable.

More Questions

Is this calculator accurate?

Yes — it uses standard, industry-typical formulas and material assumptions (150 lb/cu ft concrete, standard bag yields, common mix ratios). For structural or permitted work, always confirm final quantities with your supplier or engineer.

Do I need to create an account to use this?

No. Every calculator on ConcreteYard runs entirely in your browser, works instantly, and requires no sign-up, login, or download.

Can I use this calculator on my phone at the job site?

Yes — every tool on this site is built to work the same on a phone as it does on a desktop, so you can run the numbers standing at the job site before you call in an order.

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