Mixing Ratio Calculator

Related Calculators

Ratio parts: The relative amounts of each ingredient, such as 2:3:1. This means ingredient 1 gets 2 parts, ingredient 2 gets 3 parts, and ingredient 3 gets 1 part.

Total mixture amount: The full batch size you want before the calculator splits it across the ratio.

Ingredient amounts: The actual amounts for each ingredient, entered in order, such as 40, 60, 20.

Unit label: The unit name shown beside results, such as mL, L, oz, g, or lb. It labels results but does not convert units.

Batch multiplier: A scale factor for the whole batch. A value of 2 doubles the batch, and 0.5 makes half a batch.

Total parts: The sum of all numbers in the ratio. For 2:3:1, the total parts equal 6.

Size of one part: How much mixture one ratio part represents after dividing the final total by the total number of parts.

Share of the mixture for each ingredient: Each ingredient's percent of the final mixture.

Ratio from your amounts: The relative relationship created by the amounts you entered. Order matters, so 2:1 is different from 1:2 [3].

Mistake: Typing different units into Ingredient amounts , like some values in mL and others in oz.
Fix: Convert everything first, then enter one shared unit and write that unit in Unit label .

Mistake: Entering Ratio parts with a zero or negative value, such as 2:0 or 3:-1.
Fix: Use only positive parts greater than 0, such as 2:3 or 1:4:5.

Mistake: Using only one number in Ingredient amounts or Ratio parts .
Fix: Enter at least 2 ingredients so the calculator can build a real ratio and percentage split.

Mistake: Expecting Unit label to convert units for you.
Fix: Treat Unit label as a note only. It shows the unit next to results, but it does not change the math.

Mistake: Forgetting that Batch multiplier changes the whole recipe after the main ratio math.
Fix: Leave Batch multiplier at 1 for the original batch, use 0.5 for half, or 2 for double.

Mistake: Thinking the first number in Found ratio from your amounts belongs to the biggest ingredient no matter what.
Fix: Read the ratio in the exact same order you entered values in Ingredient amounts .

• The calculator assumes all entered amounts already use the same unit. It does not convert between mL, L, oz, g, lb, or other units.
• The math treats mixture amounts as additive. In real mixing, some substances can shrink, expand, react, or change final volume after combining.
• Whole-number ratio simplification is only applied when the found ratio is close enough to exact integer multiples. Otherwise, the ratio may stay in decimal form.
• Percentages may not add to exactly 100% after rounding, especially when you choose fewer decimal places.
• At least 2 ingredients are required. Single-value entries do not form a useful mixing ratio.
• This page is for general mixture-by-parts math. Atmospheric mixing ratio in meteorology is a different concept [2].

How the calculator works

There are 3 modes. In Split a total by ratio, the calculator uses your ratio and total batch size to find each ingredient amount. In Find ratio from amounts, it uses the entered amounts to build a ratio and percentages. In Convert percentages to ratio, it builds a ratio directly from percentages totaling 100%; it does not calculate a batch quantity. For example, 40%, 60% gives 2:3 with Simplify ratio set to Yes.

Formulas used

part size = (total mixture amount x batch multiplier) / sum of ratio parts

ingredient amount i = ratio part i x part size

ingredient percentage i = (ingredient amount i / final total amount) x 100

raw ratio i = ingredient amount i / smallest positive ingredient amount

simplified whole-number ratio = integer-scaled raw ratio divided by the greatest common divisor

Mini example

Suppose Ratio parts are 2:3, Total mixture amount is 100, and Batch multiplier is 1. The total parts are 5, so one part is 100 / 5 = 20. That gives ingredient amounts of 40 and 60. Their percentages are 40% and 60%.

If you switch to Find ratio from amounts and enter 40,60 in Ingredient amounts, the smallest amount is 40. Divide each amount by 40 to get 1 and 1.5, so the found ratio is 1:1.5. If the values are close to whole-number multiples, the calculator can simplify them into smaller whole-number parts.

How simplification works

The calculator first finds a relative ratio from the entered amounts. If Simplify ratio is on, it checks whether those relative values are close enough to whole numbers after scaling. When they are, it reduces them using the greatest common divisor so the ratio is shown in the smallest clean whole-number form.

Assumptions behind the math

The method is standard ratio-and-proportion math for splitting totals and comparing quantities [1]. The order of ingredients matters because a ratio compares one amount to another in sequence [3]. This page uses the everyday mixture meaning of mixing ratio, not the humidity-related meteorology meaning [2].

The calculator assumes one consistent unit across all amounts and treats totals as additive. Real products such as epoxy, cleaners, food mixtures, and lab solutions can behave differently in practice if density, reaction, or volume change matters.