How this calculator works
The scaling factor is new servings ÷ original servings. Each line that starts with a number, fraction or mixed number (like “1 1/2”) is multiplied by that factor and shown as a readable kitchen fraction; lines without a number are left as they are.
Factor = New servings ÷ Original servings
New amount = Original amount × Factor
Assumptions and tips
- Seasonings, leaveners and thickeners do not always scale perfectly. For big changes, adjust to taste.
- For the most reliable baking results, scale by weight using the Baker’s Percentage Calculator.
Worked example
Using the default values in the calculator above:
| Input | Value |
|---|---|
| Original servings | 4 |
| New servings | 6 |
| Result | Value |
|---|---|
| Scaling factor | 1.5 × |
Scaled ingredients:
- 3 cups all-purpose flour
- 2 1/4 tsp baking powder
- 3/4 tsp salt
- 1 1/8 cup sugar
- 3 eggs
- 1 1/2 cup milk
- 6 tbsp butter, melted
- Vanilla to taste (unchanged)
Step by step:
- Factor = 6 ÷ 4 = 1.5
- Each amount at the start of a line is multiplied by the factor and shown as a kitchen fraction.
Common mistakes to avoid
- Scaling salt, spices and leaveners blindly in very large batches — taste and adjust.
- Keeping the same pan for a doubled recipe.
Frequently asked questions
Can I scale a recipe by 1.5?
Yes — set original servings to 4 and new servings to 6, for example, and every amount is multiplied by 1.5.
Do baking times change when I double a recipe?
If you use a bigger or deeper pan, yes. Use the Cake Pan Converter to compare pan areas and check doneness early.