Mixture Calculator

This mixture calculator works out what you get when you blend two solutions of different strengths, giving you the concentration of the combined mixture in one step. You enter the amount and percentage concentration of each solution, Amount 1, Concentration 1, Amount 2 and Concentration 2, using whatever unit suits your problem as long as both amounts share the same unit and both concentrations use the same percentage basis. The calculator returns the final concentration of the blend as a percentage, the total amount you end up with, and the total solute, the actual amount of active ingredient contributed by both solutions combined. Behind the scenes it works out a weighted average: the solute from each solution is added together and divided by the combined amount, so the result leans toward whichever concentration you use more of rather than sitting exactly halfway between the two. This is the classic mixture problem from algebra, and it covers real situations too, like diluting a strong solution with water or blending two grades of fuel or alloy. Type in your own figures to check a textbook problem or a real blend, or use the worked example of 2 litres at 10 percent mixed with 3 litres at 20 percent, which gives 16 percent across 5 litres, to confirm the tool is working before you rely on it for your own numbers.

Amount 1

Concentration 1 (%)

Amount 2

Concentration 2 (%)

Final concentration = 16%

Total amount5

Total solute (amount x %)0.8

The formula

The mixture concentration is the total solute divided by the total amount: (amount1 times conc1 + amount2 times conc2) / (amount1 + amount2). It is the weighted average of the two concentrations.

Worked example

Mixing 2 litres at 10 percent with 3 litres at 20 percent gives (2 times 10 + 3 times 20) / 5 = 80 / 5 = 16 percent, in 5 litres. Enter 2, 10, 3, 20 to confirm.

Frequently asked questions

How do I find a mixture concentration?

Take the weighted average: add the solute from each solution and divide by the total amount.

Is the result halfway between the two?

Only if you use equal amounts. Otherwise it leans toward the concentration you use more of.

Does it work for any units?

Yes, as long as both amounts use the same unit and both concentrations use the same percentage basis.

Who this calculator is for

This calculator is for students, programmers and anyone needing a quick, reliable result.

What this calculator assumes

You enter valid input.
The standard algorithm is applied.
Results are rounded for display.

Formula and sources

Related calculators

Scientific Calculator: general scientific maths.
Percentage Calculator: percentages and changes.
Prime Factorisation Calculator: factor a number into primes.

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