Calculadora de Razão de Mistura
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
rA/(rA+rB) de A + rB/(rA+rB) de B → Cm
About this calculator
The Mixing Ratio Calculator determines the proportion between two components, A and B, to achieve a desired intermediate concentration. It uses the formula: rA/(rA+rB) of A + rB/(rA+rB) of B = Cm, where rA and rB are the ratios of each component and Cm is the final mixture concentration. The user inputs the concentrations of the pure components and the target concentration, and the calculator returns the required proportions.
This tool is useful in chemical labs, pharmaceutical and food industries, where it is necessary to prepare solutions with specific concentrations from stock solutions. For example, diluting a concentrated acid or adjusting the potency of an active ingredient. It is also applied in mixing paints, pesticides, and fuels.
Important precautions include checking the concentration units (percentage, molarity, etc.) and ensuring consistent input values. The calculator assumes the components are miscible and that no chemical reaction occurs between them. When diluting strong acids, always add acid to water, never the reverse, for safety.
The operation is based on the lever rule (or mixture rule), which relates the proportions of the components to the final concentration. The tool solves a linear equation to find the fraction of each component. The result is presented as a ratio or percentage, facilitating the practical preparation of the mixture.
Frequently asked questions
Can I use this calculator to mix three or more components?
No, this calculator is designed only for binary mixtures (two components). For three or more components, more advanced methods are needed.
What if the desired concentration is outside the range between the two component concentrations?
The final concentration must lie between the concentrations of the pure components. If outside, it is impossible to achieve with only these two components; you need a component with a higher or lower concentration.
Do the concentration units need to be the same for both components?
Yes, the concentrations must be in the same unit (e.g., both in percentage or both in molarity). Otherwise, the result will be incorrect.
Does this calculator account for density or volume of the components?
No, it only considers concentrations. For mixtures where density varies significantly, a mass-based or corrected volume approach may be necessary.