Ratio Serving Scale Calculator
Scale a recipe or mix written for one number of servings up or down to the servings you actually need.
How it works
Scale factor = wanted servings ÷ recipe servings · New quantity = old quantity × factor
Scaling a recipe is one multiplication: divide the servings you want by the servings the recipe makes to get a single factor, then multiply every ingredient by it. Because every ingredient is multiplied by the same number, the ratios between ingredients — the thing that actually makes the dish work — are preserved exactly. This is safer than adjusting ingredients by eye, which drifts the proportions.
Worked example
A recipe that serves 4 using 2 cups of rice and 3 cups of water, scaled to 6 servings, has a factor of 6 ÷ 4 = 1.5, giving 3 cups of rice and 4.5 cups of water — still a 2 : 3 ratio.
Frequently asked questions
Does scaling change the ratio between ingredients?
No. Multiplying every ingredient by the same factor keeps all the ratios identical — that is the whole point of scaling by a factor rather than adjusting ingredients individually.
Can I scale down to fewer servings?
Yes. If you want fewer servings than the recipe makes, the factor is less than 1 and every quantity shrinks proportionally.
Do cooking times scale the same way?
No — times, pan sizes and temperatures do not scale linearly with quantity. This tool scales ingredient amounts; adjust cooking time and vessel size by judgement.
Related calculators
This calculator is for educational purposes. Double-check important results before acting on them.