Concrete vs Cement (and Mortar): What's the Difference?
Cement is the “glue” inside concrete, not a stand-in for it: concrete is cement mixed with sand, gravel or stone and water, and one 80 lb bag of concrete mix makes approx. 0.6 ft³[1] of it.
Estimates for planning, not professional advice. Read the full notice.
Work it out for your own sizes
Work out the concrete for your own slabExample to try: Length 10 ft, Width 10 ft, Thickness 4 in
What one bag makes: concrete mix and mortar mix
What one bag of the maker's concrete mix and of its mortar mix makes, as each data sheet counts it
| Product and bag | One bag makes |
|---|---|
| Concrete mix, 80 lb bag | approx. 0.6 ft³ |
| Mortar mix, 80 lb bag, standard bricks laid | 37 bricks |
| Mortar mix, 80 lb bag, standard blocks laid | 13 blocks |
Figures in the One bag makes column are per QUIKRETE's data sheet, checked Nov 12, 2026.
Product names are trademarks of their owners. HoneyDoMath is not affiliated with, sponsored by or endorsed by these makers. Figures come from each maker's published sheets and are shown for information only.
A concrete mix is counted in the volume of concrete it makes; a mortar mix in the masonry units it lays. Both are the maker's figures.
Cement, concrete and mortar in the maker's own words
- Cement: the binder. It is the powder that reacts with water and holds the rest together.
- Concrete: portland cement with sand and coarse aggregate, gravel or stone, mixed with water.
- Mortar: masonry cement combined with sand, the bed that bonds brick and block.
Cement is actually the “glue” that holds concrete together.
Concrete is a proportional mixture of three primary components: portland cement, fine aggregate (sand) and coarse aggregate (gravel or stone).
When combined with sand, masonry cement will produce a workable mortar designed to support the weight of masonry units and provide a controlled bond.
What happens when water goes in
When water is added to the concrete mix, a chemical reaction called “Hydration” takes place. During the hydration process the cement and water harden, binding the aggregates together in a solid mass or matrix.
That reaction is what hardens the mix, which is why the time to walk on a pour is its own question: see how long concrete takes to dry and cure.
Reading the bag: concrete mix or mortar mix
QUIKRETE Concrete Mix is a pre-blended mixture of cement and aggregates for general structural uses, requiring only the addition of water
building or repairing anything out of concrete, including: Foundation walls and footings Sidewalks, curbs, steps, ramps and walkways Appliance and equipment platforms
QUIKRETE Mortar Mix is a contractor grade mortar mix designed for laying brick, concrete masonry units and stone.
Water amounts and the mix by volume are on the mix ratios page; strength by age is on the strength page.
Questions
Is cement the same as concrete?
No. Per the maker's training slides above, cement is the glue that holds concrete together, and concrete is the mixture of portland cement, sand and coarse aggregate with water.
Is a sidewalk cement or concrete?
A sidewalk is concrete. The maker's data sheet lists sidewalks among the uses of its concrete mix; cement is only the binder in that mix.
What is the difference between concrete and mortar?
The sheets describe different jobs: the concrete mix is for pouring and building in concrete, and the mortar mix is designed for laying brick, concrete masonry units and stone. The table shows what one bag of each makes.
Can I use mortar mix for a slab?
The maker's mortar sheet describes its mortar mix as designed for laying brick, concrete masonry units and stone, and its concrete sheet lists footings, sidewalks and steps among the uses of the concrete mix.
Calculate it for your project
Enter your own sizes to get the amount to buy or the layout figures, with the working shown and a page to print.
Count the concrete for your own pourSources (3)
-
QUIKRETE Concrete Mix No. 1101 data sheet (opens in new tab), The Quikrete Companies, Revised October 2022.
Manufacturer data.
“An 80 lb (36.2 kg) bag yields approximately 0.60 ft3 (17 L)”
“QUIKRETE Concrete Mix is a pre-blended mixture of cement and aggregates for general structural uses, requiring only the addition of water”
“building or repairing anything out of concrete, including: Foundation walls and footings Sidewalks, curbs, steps, ramps and walkways Appliance and equipment platforms”
Per QUIKRETE's data sheet, checked Nov 12, 2026. Figures and codes change; verify with the source. Back to where this is used (Source 1) -
QUIKRETE Mortar Mix No. 1102 data sheet (opens in new tab), The Quikrete Companies, Revised November 2020.
Manufacturer data.
“QUIKRETE Mortar Mix is a contractor grade mortar mix designed for laying brick, concrete masonry units and stone.”
“Each 80 lb (36.2 kg) bag of QUIKRETE Mortar Mix will lay up to 37 standard bricks or 13 standard (8 in by 8 in by 16 in”
Per QUIKRETE's data sheet, checked Nov 12, 2026. Figures and codes change; verify with the source. Back to where this is used (Source 2) -
QUIKRETE training module 1, Concrete & Cement: The Basics (opens in new tab), The Quikrete Companies, Dealer training slides, undated.
Manufacturer data.
“Cement is actually the “glue” that holds concrete together.”
“Concrete is a proportional mixture of three primary components: portland cement, fine aggregate (sand) and coarse aggregate (gravel or stone).”
“When combined with sand, masonry cement will produce a workable mortar designed to support the weight of masonry units and provide a controlled bond.”
“When water is added to the concrete mix, a chemical reaction called “Hydration” takes place. During the hydration process the cement and water harden, binding the aggregates together in a solid mass or matrix.”
Per QUIKRETE's published data, checked Nov 12, 2026. Figures and codes change; verify with the source. Back to where this is used (Source 3)
These are summaries of what the sources say, not professional advice. Codes and product data change. Check with your building department and the product label about your own project.