Sakrete Concrete Calculator
Calculate how many bags of Sakrete concrete mix you need — enter your slab dimensions to get the bag count for 60 and 80 lb bags, with a waste allowance and an estimated cost.
United States — national average · 2026 prices
Material only unless stated as installed. Excludes tax, permits and local labour. Verify with local suppliers — see how we calculate.
How this calculator works
Every figure above comes from the formula below, applied to the assumptions listed. Nothing is looked up from a hidden table — you can reproduce the result by hand.
Formula
cubic feet = length × width × thickness (in) ÷ 12 × (1 + waste ÷ 100)
bags = cubic feet ÷ bag yield, rounded up
bag yield: 80 lb = 0.60 · 60 lb = 0.45 · 40 lb = 0.30 cu ft
Assumptions & limits
- Sakrete standard concrete mix is commonly stocked in 60 and 80 lb bags, yielding about 0.45 and 0.60 cu ft — so roughly 60 or 45 bags per cubic yard.
- Sakrete's 40 lb size is less commonly stocked than Quikrete's, so plan around the 60 and 80 lb bags unless you have confirmed local availability.
- Yields are for the general-purpose mix; Sakrete's Fast-Setting and High-Strength products differ — check the bag.
- Bag yields follow the QUIKRETE Concrete Mix data sheet. Other brands and mix types (fast-setting, high-early-strength) yield slightly differently — check your bag.
- Bag prices assume $6.00 per 80 lb, $4.75 per 60 lb and $3.75 per 40 lb bag.
- Default waste allowance is 10%, higher than the ready-mix default because part-bags and spillage cost proportionally more on small jobs.
- Counts are rounded up to whole bags — you cannot buy two thirds of a bag.
- For a post hole, the figure is the hole volume. Subtract the post itself for a closer number.
Worked example
An 8 ft × 8 ft shed pad, 4 inches thick, 10% waste, in Sakrete 80 lb bags
- Cubic feet = 8 × 8 × 4 ÷ 12 = 21.3, plus 10% waste = 23.5 cu ft
- 80 lb bags = 23.5 ÷ 0.60 = 39.1 → 40 bags
- 60 lb bags = 23.5 ÷ 0.45 = 52.1 → 53 bags
- Cross-check: 23.5 cu ft ÷ 27 = 0.87 yd³, and Sakrete lists ~45 × 80 lb bags per yd³
Result:40 × 80 lb bags of Sakrete mix. At this count, pricing a ready-mix short load is worth a phone call.
Built and maintained by Christoph Ballmer, Honeygoat GmbH
Method and constants last checked against the calculator code on August 17, 2026. Independent trade review is not yet in place for this calculator — see how we handle review.
Read the site-wide calculation methodology · estimate vs. quote and safety limits
How many bags of Sakrete concrete do I need?
Sakrete is a long-running bagged concrete brand sold at many home centers and lumberyards. Its standard concrete mix commonly comes in 60 and 80 lb bags, yielding about 0.45 and 0.60 cubic feet each — the same yields used across general-purpose mixes, so about 60 or 45 bags per cubic yard. This calculator sizes a Sakrete job from your dimensions.
To size it, the calculator takes your slab volume and divides by the bag yield, rounding up with a waste allowance. Sakrete concrete mix is sold in 60 and 80 lb bags, and the result shows the count for each size so you can pick whichever your store stocks or you can lift.
bags = (length × width × thickness ÷ 12, in cu ft) ÷ bag yield
For a bigger pour, compare Sakrete bags against ready-mix with the concrete calculator, or price a delivery with the concrete cost calculator.
Concrete bag calculators by brand
Size a job with another concrete brand:
Frequently asked questions
How many bags of Sakrete concrete do I need?
Find your slab volume in cubic feet (length × width × thickness, all in feet), then divide by the bag yield: about 0.60 cu ft for an 80 lb bag, 0.45 for 60 lb and 0.30 for 40 lb. Sakrete concrete mix comes in 60 and 80 lb bags. The calculator above does this from your dimensions and rounds up.
How many Sakrete bags make a cubic yard?
A cubic yard is 27 cubic feet, so it takes about 45 × 80 lb bags, 60 × 60 lb bags, or 90 × 40 lb bags of Sakrete concrete mix — the same as any general-purpose mix at standard yields.
Sakrete or Quikrete — does the brand matter?
For general-purpose concrete mix, barely: yields and strengths are comparable, and both publish them on the bag. Buy whichever your store stocks at the better price, and check the printed yield and PSI on the actual bag — that number beats any brand assumption, including the ones this calculator defaults to.
Which Sakrete mix should I use for a slab?
Sakrete's High-Strength 5000 Plus is the slab-and-driveway choice — higher strength and a faster early cure than the standard mix. The regular concrete mix handles pads, footings and post setting fine. For anything in a freeze-thaw climate that sees deicing salt, the higher-strength mix is the safer call.
How many bags of Sakrete do I need for a fence post?
A typical 4-inch post in a 10-inch hole about 2 ft deep takes roughly one and a half to two 80 lb bags. Wider augers and deeper frost lines push it up fast — enter the hole as a round column in the concrete calculator (diameter and depth) and subtract the post itself for a close figure.
How many bags of concrete for a fence post?
For a typical 4-inch post in a 10-inch-wide hole 2 feet deep, plan on roughly one to two 50–60 lb bags per hole. Wider or deeper holes need more. Enter the hole as a round column above (diameter and depth) to size it exactly, and remember to subtract the post itself for a close figure.