Sand
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Mix design
Concrete mix ratio calculator
Turn a target volume into the cement, sand and aggregate it takes — for mixing concrete from scratch by a chosen ratio.
Mix & volume
FIG. 01Dry ingredients bulk up to about 1.54× the finished wet volume. A 94 lb bag of Portland cement is roughly 1 ft³. Add water per the mix design — typically a 0.4–0.6 water-cement ratio.
Cement needed
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— of cement by volume
Aggregate
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How this is calculated
A common general-purpose mix is 1:2:3 — one part cement, two parts sand, three parts aggregate, by volume. Higher-strength mixes use more cement (e.g. 1:1.5:3). This calculator converts your target volume into the amount of each ingredient.
dry volume = wet volume × 1.54 · each part = dry volume × (its ratio ÷ sum of ratios)
This is for mixing from raw materials. Buying bags instead? Use the bag calculator. See methodology for the bulking factor.
FAQ
What is the ratio for mixing concrete?
A common general-purpose mix is 1:2:3 — one part cement, two parts sand, three parts aggregate, by volume. Higher-strength mixes use more cement (e.g. 1:1.5:3). This calculator converts your target volume into the amount of each ingredient.
How much cement, sand and gravel for 1 cubic yard?
For a 1:2:3 mix, about 1 cubic yard of concrete needs roughly 6–7 bags of 94 lb cement plus proportional sand and aggregate, because dry materials bulk up about 1.54× the finished volume. Enter your volume to see exact amounts.
Should I mix from scratch or use bagged mix?
For small jobs, pre-blended bags are simpler and more consistent. Mixing from raw cement, sand and aggregate makes sense only for larger volumes or when you need a specific mix design — and even then, ready-mix is usually better for structural work.