Cement / Sand / Aggregate Mix Calculator
Mix by Concrete Volume
Calculate cement, sand, and aggregate from target concrete volume
Mix by Slab Dimensions
Calculate mix materials from slab length, width, and thickness
Formula
Dry Volume = Wet Volume x 1.54 | Cement = (C / Total Parts) x Dry Volume | Sand = (S / Total Parts) x Dry Volume | Aggregate = (A / Total Parts) x Dry Volume
Frequently Asked Questions
What is the standard concrete mix ratio?
The most common mix ratio is 1:2:3 (1 part cement, 2 parts sand, 3 parts aggregate) which produces approximately 3,000 PSI concrete. For stronger concrete (4,000 PSI), use 1:1.5:3. For general foundations, 1:2:4 is adequate.
How many bags of cement do I need per cubic yard?
For a standard 1:2:3 mix, you need approximately 7 bags (94-lb) of Portland cement per cubic yard of concrete. For a stronger 1:1.5:3 mix, you need about 8-9 bags. Pre-mixed bags (like Quikrete) contain all ingredients already blended.
What is the water-to-cement ratio?
The water-to-cement ratio by weight should be 0.40-0.50 for most applications. A ratio of 0.45 is common for a good balance of workability and strength. Less water makes stronger concrete but is harder to work with. Never exceed 0.60.
You may also need
~
Concrete Calculator
Free concrete calculator. Calculate how many bags or cubic yards of concrete you need for slabs, footings, columns, and stairs.
Everyday~
Concrete Block Fill Calculator
Calculate the volume of concrete or grout needed to fill CMU (concrete masonry unit) block cores. Estimate cubic yards and bags for block wall fills.
Everyday~
Concrete Patio Volume & Cost Calculator
Calculate the concrete volume and estimated cost for a patio project. Includes material, labor, and finishing costs for standard and stamped concrete.
Everyday