What it is
This calculator lets home chefs, bakers and dietitians easily scale any recipe up or down while keeping the nutrient balance correct. It takes a base batch’s total calories, fat, and protein, along with how many servings it originally yields, and computes how much each of those nutrients will be per serving after expansion or reduction. A percentage waste factor can be entered to subtract what is typically discarded during preparation – for instance lost dough when shaping cakes or trimmed vegetables. By preserving the proper proportion of macronutrients, nutrition labels remain accurate even after you adjust portion sizes, which is essential for diet tracking, meal‑planning and serving larger groups without unintentional calorie overages.
How to use it
Enter the original number of servings for your recipe in 'Original Servings' and how many servings you plan to produce in 'Target Servings'. Specify what percentage of the batch will be discarded; a common value is 5% but enter 0 if none. Input the total calories, fat (in grams) and protein (in grams) that the recipe totals for those original servings – these values can come from nutrition databases or the product labels used in the recipe. Click calculate. The calculator displays calories, fat and protein per serving after scaling and waste adjustments. Use these figures to update meal plans or dietary logs. If you need ingredient‑level detail, scale each individual quantity by the same factor shown here.
Worked example
1. Original recipe yields 4 servings and contains 2,000 kcal, 80 g fat and 100 g protein. 2. Desired batch is 6 servings → scaling factor sf = 6 ÷ 4 = 1.5. 3. Waste % = 5 % → waste multiplier wm = 1 – 0.05 = 0.95. 4. Scale totals: calories = 2,000 × 1.5 × 0.95 = 2,850 kcal; fat = 80 × 1.5 × 0.95 = 114 g; protein = 100 × 1.5 × 0.95 = 142.5 g. 5. Divide by new servings to get per‑serving values: • Calories: 2,850 ÷ 6 = 475 kcal. • Fat: 114 ÷ 6 = 19 g. • Protein: 142.5 ÷ 6 ≈ 23.75 g. These are the nutrition numbers you can now use for diet plans or label updates.
Inputs
- Original Servings: 4
- Target Servings: 6
- Waste %: 5
- Total Calories: 2000
- Total Fat: 80
- Total Protein: 100
Result
- Calories/Serving: 475
- Fat/Serving: 19
- Protein/Serving: 23.75
Frequently asked questions
I have the ingredient lists and their per‑100 g values – can I get per‑ingredient scaling instead of total nutrition?
This tool is designed for batch‑level scaling; it takes total nutrient figures as input. For itemized scaling you would need a more complex spreadsheet that tracks each ingredient’s contribution and recalculates the totals afterward.
What if my waste is exactly 100%? Will the calculator give negative nutrition?
The logic clamps any waste multiplier less than zero to zero, so all outputs become zero rather than negative numbers. This mirrors real‑world behavior where no usable portions remain after a 100% discard.