BakeSpan / Guide
Scale the recipe. Keep the assumptions.
Scaling ingredients is multiplication. Making a successful bake still requires judgment about the recipe, equipment, and process.
Use one definition of yield
If a recipe makes 8 equal servings and you want 12 equal servings, use 12 divided by 8. The factor is 1.5. For an ingredient listed as 120 grams, the new amount is 180 grams.
New amount = original ingredient amount × factor
Do not compare 8 servings on one side with 12 grams on the other. Both yield numbers must represent the same thing. A serving-size change is a separate decision.
Keep units attached to quantities
Doubling one cup produces two of the same cup measure. It does not establish the ingredient’s weight in grams. US customary cups, metric cups, and other conventions differ. Ingredient preparation also affects mass per volume. BakeSpan deliberately scales your existing measure without guessing a density or changing a cup standard.
Do not silently round eggs
If a factor produces 1.5 eggs, rounding to two changes the recipe. One practical way to measure a fraction is to beat an egg, weigh its actual contents without the shell, and use the required fraction. Do not assume that every egg has the same mass. This tool keeps the fractional count and does not invent an egg-weight conversion.
What does not scale automatically
Baking time, mixing behavior, vessel capacity, fermentation, and food safety are not determined by the yield ratio. Chemically sensitive ingredients can require recipe-specific judgment. A numerical ratio does not prove that a recipe will behave identically at a much larger scale.
Save a reproducible worksheet
Keep the original quantities, target yield, unit convention, and any decisions about rounding. BakeSpan exports a CSV for tabular quantities and a versioned JSON file for reopening the project. A saved browser snapshot is convenient, but clearing browser storage removes it. Use a downloaded backup for portability.
Further reading: Calculation method, sources, and limitations. These examples are arithmetic explanations, not tested recipes.