QUIKRETE / Sakrete / every bag size

Concrete Bag Calculator

A 12 x 12 ft slab 4 in thick is 48 cu ft; with 10% extra that comes to 88 bags of 80 lb concrete mix, 118 of 60 lb or 176 of 40 lb, by QUIKRETE's printed yields.

Sources checked Oct 13, 2026

Your estimate

88 bags of 80 lb

48 cu ft (1.78 cu yd) plus 10%, QUIKRETE Concrete Mix.

Bag sizes comparedLive sketch

Whole bags to buy, including 10% extra

60 lb bags107 with no extra
118 bags
50 lb bags128 with no extra
141 bags
40 lb bags160 with no extra
176 bags

Every QUIKRETE and Sakrete bag for this pour is in the table below.

Bags of 80 lb for 48 cu ft, rounded up: bare, and with 10% extra.
Product	Bag	Yield	Bare	With extra
QUIKRETE Concrete Mix (No. 1101)	80 lb	0.6 cu ft	80	88
QUIKRETE 5000 Concrete Mix (No. 1007)	80 lb	0.6 cu ft	80	88
QUIKRETE Crack Resistant Concrete Mix (No. 1006)	80 lb	0.6 cu ft	80	88
Sakrete 5000 Plus Concrete Mix	80 lb	0.6 cu ft	80	88
Sakrete High-Strength Concrete Mix	80 lb	0.6 cu ft	80	88
Sakrete Crack-Resistant Concrete Mix	80 lb	0.6 cu ft	80	88

Every product and bag size (25 rows)

Bags for 48 cu ft, rounded up: bare, and with 10% extra.
Product	Bag	Yield	Bare	With extra
QUIKRETE Concrete Mix (No. 1101)	40 lb	0.3 cu ft	160	176
QUIKRETE Concrete Mix (No. 1101)	50 lb	0.375 cu ft	128	141
QUIKRETE Concrete Mix (No. 1101)	60 lb	0.45 cu ft	107	118
QUIKRETE Concrete Mix (No. 1101)	80 lb	0.6 cu ft	80	88
QUIKRETE Concrete Mix (No. 1101)	90 lb	0.675 cu ft	72	79
QUIKRETE 5000 Concrete Mix (No. 1007)	50 lb	0.375 cu ft	128	141
QUIKRETE 5000 Concrete Mix (No. 1007)	60 lb	0.45 cu ft	107	118
QUIKRETE 5000 Concrete Mix (No. 1007)	80 lb	0.6 cu ft	80	88
QUIKRETE Fast-Setting Concrete Mix (No. 1004)	50 lb	0.375 cu ft	128	141
QUIKRETE Fast-Setting Concrete Mix (No. 1004)	60 lb	0.45 cu ft	107	118
QUIKRETE Commercial Grade FastSet Concrete Mix (No. 1004-51)	70 lb	0.52 cu ft	93	102
QUIKRETE Crack Resistant Concrete Mix (No. 1006)	50 lb	0.375 cu ft	128	141
QUIKRETE Crack Resistant Concrete Mix (No. 1006)	60 lb	0.45 cu ft	107	118
QUIKRETE Crack Resistant Concrete Mix (No. 1006)	80 lb	0.6 cu ft	80	88
Sakrete 5000 Plus Concrete Mix	50 lb	0.38 cu ft	127	139
Sakrete 5000 Plus Concrete Mix	60 lb	0.47 cu ft	103	113
Sakrete 5000 Plus Concrete Mix	80 lb	0.6 cu ft	80	88
Sakrete High-Strength Concrete Mix	40 lb	0.3 cu ft	160	176
Sakrete High-Strength Concrete Mix	60 lb	0.45 cu ft	107	118
Sakrete High-Strength Concrete Mix	80 lb	0.6 cu ft	80	88
Sakrete High-Strength Concrete Mix	90 lb	0.66 cu ft	73	80
Sakrete Fast Setting Concrete Mix	50 lb	0.38 cu ft	127	139
Sakrete Crack-Resistant Concrete Mix	50 lb	0.38 cu ft	127	139
Sakrete Crack-Resistant Concrete Mix	60 lb	0.45 cu ft	107	118
Sakrete Crack-Resistant Concrete Mix	80 lb	0.6 cu ft	80	88

How to figure how many bags of concrete you need

Find the volume: 12 x 12 ft x 4 in / 12 = 48 cu ft (1.78 cu yd). A volume you already know goes in as cubic yards; footings, steps and round forms are worked out on the concrete calculator.
Add the extra: 48 x 1.1 = 52.8 cu ft. Set it to 0 to see the bare count.
Divide by the yield printed for that bag and round up: 52.8 / 0.6 = 88, so 88 bags of 80 lb QUIKRETE Concrete Mix. For the cubic feet a bag makes, by brand and weight, see how many cubic feet in a bag of concrete.
The table repeats the last step for every product and bag weight we have a data sheet for, because a 50 lb bag of one brand and of another can yield different volumes.
Check the weather before you pour: Sakrete's data sheet prints 40 to 90 °F for the air, the mix and the base. The slab planner shows which months of your city's average temperatures fall inside that range. See when you can pour in your city.

With the extra set to 0 we get 160, 107 and 80 bags of 40, 60 and 80 lb. Sakrete's own slab calculator printed 160, 107 and 80 for the same slab, and 73 of its 90 lb bag where our table says 73. diycalcs, with its waste set to 0, gave 1.78 cu yd, 80 bags of 80 lb and 107 of 60 lb.

Yields we use, by product

QUIKRETE Concrete Mix (No. 1101): 40 lb: 0.3 cu ft, 50 lb: 0.375 cu ft, 60 lb: 0.45 cu ft, 80 lb: 0.6 cu ft, 90 lb: 0.675 cu ftQUIKRETE Concrete Mix 1101 data sheet (Oct 2022)
QUIKRETE 5000 Concrete Mix (No. 1007): 50 lb: 0.375 cu ft, 60 lb: 0.45 cu ft, 80 lb: 0.6 cu ftQUIKRETE 5000 Concrete Mix 1007 data sheet (Nov 2022)
QUIKRETE Fast-Setting Concrete Mix (No. 1004): 50 lb: 0.375 cu ft, 60 lb: 0.45 cu ftQUIKRETE Fast-Setting Concrete Mix 1004 data sheet (Nov 2025); QUIKRETE Fast-Setting Concrete Mix 1004-60 data sheet
QUIKRETE Commercial Grade FastSet Concrete Mix (No. 1004-51): 70 lb: 0.52 cu ftQUIKRETE FastSet Concrete Mix 1004-51 data sheet (Aug 2021)
QUIKRETE Crack Resistant Concrete Mix (No. 1006): 50 lb: 0.375 cu ft, 60 lb: 0.45 cu ft, 80 lb: 0.6 cu ftQUIKRETE Crack Resistant Concrete Mix 1006 data sheet (Dec 2021)
Sakrete 5000 Plus Concrete Mix: 50 lb: 0.38 cu ft, 60 lb: 0.47 cu ft, 80 lb: 0.6 cu ftSakrete 5000 Plus Concrete Mix data sheet (2023)
Sakrete High-Strength Concrete Mix: 40 lb: 0.3 cu ft, 60 lb: 0.45 cu ft, 80 lb: 0.6 cu ft, 90 lb: 0.66 cu ftSakrete High-Strength Concrete Mix data sheet (2023)
Sakrete Fast Setting Concrete Mix: 50 lb: 0.38 cu ftSakrete Fast Setting Concrete Mix data sheet (2018)
Sakrete Crack-Resistant Concrete Mix: 50 lb: 0.38 cu ft, 60 lb: 0.45 cu ft, 80 lb: 0.6 cu ftSakrete Crack-Resistant Concrete Mix data sheet (2023); Sakrete Crack-Resistant Concrete Mix product page
Extra over the volume: 10% unless you change itSakrete concrete calculators page

Bags of concrete for small slabs and pads

80 lb bags of QUIKRETE Concrete Mix at 4 in thick, rounded up: bare, and with 10% extra.
Pad	Volume	Bare	With extra
3 x 3 ft	3 cu ft	5	6
4 x 4 ft	5.33 cu ft	9	10
4 x 6 ft	8 cu ft	14	15
4 x 8 ft	10.67 cu ft	18	20
5 x 5 ft	8.33 cu ft	14	16
6 x 6 ft	12 cu ft	20	22
8 x 8 ft	21.33 cu ft	36	40
10 x 10 ft	33.33 cu ft	56	62

Where sources disagree

Sakrete 5000 Plus, 60 lb: bags for the 12 x 12 ft slab 4 in thick with 10% extra

0.47 cu ft a bag: 113 bagsSakrete 5000 Plus Concrete Mix data sheet (2023)
0.45 cu ft a bag: 118 bagsSakrete 5000 Plus Concrete Mix product page

Sakrete's data sheet and its product page print two yields for one bag; the table uses the data sheet and shows the page's count here.

A 90 lb bag: bags for the same slab

QUIKRETE, 0.675 cu ft: 79 bagsQUIKRETE Concrete Mix 1101 data sheet (Oct 2022)
Sakrete, 0.66 cu ft: 80 bagsSakrete High-Strength Concrete Mix data sheet (2023)

The two are different products of the same weight; buy by the yield printed on the bag in your cart.

Concrete bag questions

How many bags of concrete do I need for a 12 x 12 slab?

At 4 in thick, 80 bags of 80 lb cover the bare 48 cu ft, and 88 cover it with 10% to spare. In 60 lb bags the same counts are 107 and 118.

How many bags of concrete for a 4x4, 4x8 or 5x5 pad?

At 4 in thick and with 10% extra, a 4 x 4 ft pad takes 10 bags of 80 lb (9 with none), a 4 x 8 ft pad 20 (18), a 5 x 5 ft pad 16 (14). The table above lists more small sizes.

How many bags of concrete for a footing or a post hole?

A round footing 12 in across and 3 ft deep holds 2.36 cu ft: 4 bags of 80 lb. Form tubes are worked out by the Sonotube concrete calculator, a fence post in its hole by the fence post concrete calculator.

Why add 10 percent to the bag count?

Sakrete's calculators page advises 10% over the computed volume. QUIKRETE's calculator adds none: its 100 sq ft slab at 4 in comes to 56 bags of 80 lb, the bare volume rounded up. The box above takes any percentage, 0 included.

Do QUIKRETE and Sakrete 80 lb bags make the same amount?

Yes: both print 0.6 cu ft for an 80 lb bag, so this slab takes 88 of either brand with the extra. Their 50 lb bags differ slightly, 0.375 against 0.38 cu ft.

How many bags of fast-setting concrete for a slab?

QUIKRETE prints the same 0.375 cu ft for its 50 lb Fast-Setting bag as for its 50 lb Concrete Mix, so the 12 x 12 ft slab takes 141 of them with 10% extra. Its 70 lb commercial FastSet bag yields 0.52 cu ft: 102 bags.

A planning aid, not an engineering calculation: your local code and building inspector have the final word. Terms