Mixture Calculator

This mixture calculator works out the concentration you get when two solutions of different strengths are blended together. Enter the amount and the percentage concentration of each, and the calculator returns the concentration of the mixture and the total amount. The result is the weighted average of the two concentrations, weighted by how much of each you use, because the solute from both is shared across the combined volume. Mixture problems are a staple of algebra and chemistry, covering things like diluting a solution or blending two grades of fuel or alloy. The formula, a worked example and the assumptions are below.

Amount 1

Concentration 1 (%)

Amount 2

Concentration 2 (%)

Total amount

Total solute (amount x %)

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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