Cement Calculator
Find the cubic yards or m³ of concrete for your job. Then use the tables to turn it into bags of cement, sand and stone.
Measure your project
Your answer
That is 29.3 cubic feet, or 0.83 m³. We added 10% extra.
If you buy bags
These bags are 30 kg premix, with the sand and stone already in. For bags of cement, see the tables below.
If you order a truck (ready-mix)
Ask for 1.00 m³ (about 1.31 cubic yards). The smallest load on Ontario plant lists is 1 m³, so we price at least that.
This is a guide. For footings, posts or slabs that hold weight, check your local building rules or ask a builder or engineer.
Which costs less?
But you must mix 59 bags by hand. That is 1.8 tonnes to lift.
Ready-mix (25 MPa): the middle of 4 lists from 3 companies in Ontario and Calgary. Premix bags: the middle of 8 prices at 5 Ontario stores. October 2026, before GST/HST.
Quick answers
- 40 kg bags of cement per m³
- 10 by Sakrete's sheet, or 7.5 by Marco's. The makers differ, so we show both.
- Per cubic yard of concrete
- About 7.65 bags at Sakrete's rate, or 5.73 at Marco's.
- Mix by volume
- 1 cement : 2.5 sand : 2.5 stone, says Sakrete. The building code (Part 9) mix with 20 mm stone is 1 : 1.75 : 2.5.
- Price of a 40 kg bag
- $25.85, the middle of 4 sellers. Ontario stores charge about $23.70 (3 stores).
- 10 × 8 ft pad, 4 in thick
- 0.83 m³ with 10% extra. That takes 9 bags of cement at Sakrete's rate.
How to work it out
- Use the calculator to find the cubic yards or m³ of concrete.
- Multiply the m³ by 10 for 40 kg bags of cement. Round up.
- For Sakrete's mix, multiply the m³ by 0.7. That gives the m³ of sand, and of stone.
- In cubic yards, use 7.65 bags for each yard.
10 × 8 × 4 ÷ 12 = 26.7 cubic feet
26.7 + 10% = 29.3 cubic feet = 0.83 m³
0.83 × 10 = 8.3 → 9 bags of cement
0.83 × 0.7 = 0.58 m³ of sand, and the same of stone
Cement content: bags, sand and stone per m³
Portland cement comes in 40, 30 and 20 kg bags. 40 kg is the usual size. Canada calls general-use cement "GU", but many store listings still say "Type 10".
US guides count 94 lb bags of Portland cement. Our 40 kg bag is about 88 lb, so use 40 kg here.
| Mix | Bags per m³ | Bags per yard | Sand, m³ | Stone, m³ |
|---|---|---|---|---|
| Sakrete, 1 : 2.5 : 2.5 | 10 | 7.65 | 0.7 | 0.7 |
| Code mix, 1 : 1.75 : 2.5 | 10 | 7.65 | 0.49 | 0.7 |
| Marco (mix not given) | 7.5 | 5.73 | – | – |
About figures, by volume. Sand and stone are loose and damp. The code mix row uses Sakrete's 10 bags per m³.
Sakrete says one 40 kg bag makes about 0.1 m³ (3.5 cubic feet). Marco says 120 kg makes 0.4 m³. That is why the counts differ.
The cement content is the cement in each m³ of concrete. At Sakrete's rate it is about 400 kg, and at Marco's about 300 kg.
The code's own site mix
The building code (Part 9) gives a mix for plain concrete you make on site. One part is one 40 kg bag of cement, about 28 L.
| Biggest stone | Cement | Damp sand | Stone |
|---|---|---|---|
| 14 mm | 1 bag (28 L) | 49 L | 56 L |
| 20 mm | 1 bag (28 L) | 49 L | 70 L |
| 28 mm | 1 bag (28 L) | 56 L | 84 L |
| 40 mm | 1 bag (28 L) | 56 L | 98 L |
From Table 9.3.1.7, as printed in the BC Building Code 2018. Check the code where you live.
We use the 20 mm row. That is about the ¾ in stone in Sakrete's mix. Sakrete adds 20–23 L of water per bag for its own mix.
Cement for common jobs
Each job has 10% extra. Compare the cement bags with ready-to-use premix bags, which already hold the sand and stone.
| Job | m³ | Cement (10/m³) | Cement (7.5/m³) | Premix bags |
|---|---|---|---|---|
| Slab 10 × 8 ft, 4 in thick | 0.83 | 9 | 7 | 59 |
| 4 piers, 10 in wide, 4 ft deep | 0.27 | 3 | 3 | 20 |
| Footing 40 ft long, 10 × 4 in | 0.35 | 4 | 3 | 25 |
Footings and piers hold weight. Check your local building rules or ask a builder or engineer.
A bag of cement makes about 7 times as much concrete as a bag of premix. But you must buy and mix the sand and stone too.
Mix your own, premix or a truck?
| Way | Cost | Not counted |
|---|---|---|
| 10 bags of cement (Sakrete's rate) | $258.50 | Sand, stone and mixing |
| 7.5 bags of cement (Marco's rate) | $193.88 | Sand, stone and mixing |
| 72 bags of 30 kg premix | $503.28 | Mixing |
| Ready-mix, 25 MPa | $255.50 | Small-load and plant fees |
Cement: $25.85 a bag, the middle of 4 sellers. Premix: $6.99, 5 Ontario stores. Ready-mix: Ontario and Calgary lists.
The cement alone costs about as much as 1 m³ of ready-mix. Sand, stone and mixing come on top, plus a cement mixer if you rent one. On a small job, a truck's small-load fee can change that.
Masonry cement is for mortar
Masonry cement makes mortar. It is mostly mixed with sand, 1 part to 2¼ to 3 parts. One Type S mix adds ½ part Portland cement too. Ontario stores sell 30–33 kg bags of Type S masonry cement for about $23.66 (only 3 stores). Pre-mixed mortar already holds the sand, and a 30 kg bag makes about 18 L.
See the concrete block calculator for mortar by the wall.
Questions people ask
How many 40 kg bags of cement make 1 m³ of concrete?
10 bags of 40 kg, says Sakrete Canada. Marco's sheet works out to 7.5. Our tables use the higher count.
How many bags of cement are in a yard of concrete?
About 7.65 bags of 40 kg, so buy 8. At Marco's rate it is 5.73, so buy 6.
How do I work out cement in yards?
Multiply the square feet by the thickness in inches. Divide that by 324, and you have cubic yards. Then multiply by 7.65 for bags.
What is the mix ratio for concrete?
Sakrete uses 1 part cement, 2.5 parts sand and 2.5 parts ¾ in stone. The building code (Part 9) uses 1 : 1.75 : 2.5 with 20 mm stone.
How much sand and stone for 1 m³ of concrete?
About 0.7 m³ of sand and 0.7 m³ of stone, with Sakrete's mix. Measure them loose and damp.
How much water goes in a 40 kg bag of cement?
20–23 L, says Sakrete, for its sand and stone mix.
How much is a bag of cement in Canada?
About $25.85 for 40 kg, before tax. That is the middle of 4 sellers in Ontario and BC, and one price was a sale.
What do you mix masonry cement with?
Mostly sand. The building code (Part 9) mixes 1 part masonry cement with 2¼ to 3 parts damp sand. One Type S mix also adds ½ part Portland cement.
Where our numbers come from
- Cement bags and mix: Sakrete Portland Cement (Canada) data sheet
- Cement per cubic metre: Marco Portland GU data sheet (Quebec)
- Concrete strength and site mixes: BC Building Code 2018, Section 9.3 (Part 9)
- Cement price: 4 Canadian stores, 40 kg (Oct 2026)
- Store prices: Ontario Home Depot, RONA, Home Hardware and Chamberlain Timber Mart (Oct 2026)
- Mortar type and joints: BC Building Code 2018, Section 9.20
- Mortar per bag: Sakrete Mortar Mix Type S (Canada) data sheet
- Bag size: Sakrete Canada Concrete Mix (30 kg makes 0.014 m³, or ½ cubic foot)
- Bag sizes: Quikrete Concrete Mix, Canadian data sheet (30 kg = 14 L, 25 kg = 11.7 L)
- Ready-mix price: the middle of 4 prices from 3 companies (25 MPa, Oct 2026, before tax)
- Small-load and winter fees: Dufferin Concrete 2026 price list (Ontario)
- Small-load fees: CBM Toronto-area price list
- Concrete strength: RMCAO residential concrete guide
- Driveways and garage slabs: Concrete Manitoba (thickness, base, steel)
- Extra for spills: Sakrete slab calculator (10%)
- Cement per cubic yard: Quikrete Portland Cement data sheet (5 to 6 bags of 94 lb)
Made by BuildersCount. Last checked 4 Oct 2026.
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