Concrete Mix Ratio Calculator
Split a mix volume among cement, sand, and gravel using a configurable ratio.
Split a mix by ratio
Enter the volume to distribute and a ratio such as 1:2:3. The calculator totals the parts and assigns each component its share.
Component = volume × component parts ÷ total parts
Optional cement weight and bags
When you know the applicable bulk density, convert cement volume to kg and divide it into 25, 40, 50 kg, or custom bags. Density remains visible and editable; no hidden value is used.
The ratio remains configurable and is not a structural mix recommendation.
Frequently asked questions
What does 1:2:3 mean?
One equal-volume part cement, two sand, and three gravel.
How are bags calculated?
Cement volume is multiplied by entered density and divided by selected bag weight, rounding upward.
Is this a recommended structural mix?
No. It only distributes the ratio you enter.
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