How to Scale a Recipe Up or Down

You found a recipe that serves 4, but you are cooking for 10. Or it makes 24 cookies and you want a quiet dozen. Scaling a recipe is mostly simple arithmetic — with a few traps worth knowing.

The basic math

Find your scaling factor: divide the servings you want by the servings the recipe makes. Want 10 from a recipe of 4? That is 10 ÷ 4 = 2.5. Multiply every ingredient by 2.5.

The arithmetic is easy in grams and awkward in cups. "1¾ cups times 2.5" is a headache; "220 g times 2.5" is not. This is one more reason to bake by weight.

What scales cleanly

Flour, sugar, butter, liquids, eggs, and most add-ins scale directly with the factor. Round egg counts to whole eggs and adjust slightly if needed.

What does not scale linearly

• Salt and strong spices. Scale up a little less than the factor, then taste — seasoning grows stronger faster than you expect.
• Leavening. In big jumps, baking soda and powder may need a slight reduction or the bake can taste soapy and over-risen.
• Baking time. Time barely changes; pan size does. A doubled cake batter needs a bigger pan or two pans, not one pan baked twice as long.
• Alcohol and extracts. Scale conservatively — vanilla and liquor intensify.

Pan size matters most

If you double a batter, the depth — not just the area — changes how it bakes. Keep the batter depth similar to the original by choosing a larger pan or splitting between two. Our pan size converter shows which pans hold equivalent volumes.

A practical routine

1. Convert the recipe to grams with our converters.
2. Multiply by your scaling factor (or use the recipe scaler).
3. Ease back slightly on salt, spice, and leavening for big changes.
4. Pick a pan that keeps the batter at a similar depth.