To double a recipe, multiply the main ingredients (flour, sugar, butter, liquids, meat, vegetables) by two, then treat everything else as a judgment call. Salt, strong spices, and leavening often need a little less than a full double, and the pan size and cooking time almost always change. Halving works the same way in reverse, with one extra puzzle: what to do with half an egg.
That's the short answer. The longer one explains why your doubled brownies came out gooey in the middle. Scaling isn't just math. It's math plus physics: a bigger batch holds heat, evaporates, and browns differently. Here's the system we use.
Before you grab a calculator, read the ingredient list and split it into two buckets.
Multiply straight across:
Multiply, then taste and adjust:
For the second bucket, a good rule of thumb is to start with about one and a half times the original amount when you're doubling, then taste and add more toward the full double. You can always add salt. You cannot take it out.
Write down your scaled numbers before you start. Doing math with butter on your hands is how a tablespoon becomes a teaspoon.
Halving is where measurements get weird. Half of 1/3 cup? Half of 3 eggs? These conversions cover most of what you'll run into:
So half of 1/3 cup is 2 tablespoons plus 2 teaspoons. Half of 1/4 cup is 2 tablespoons. Half of 1 tablespoon is 1 1/2 teaspoons.
If your recipe gives weights (grams or ounces), scaling is far easier: just multiply or divide. A kitchen scale is the best tool for scaling accurately.
Beat the egg until yolk and white are fully mixed, then use roughly half, about 2 tablespoons for a large egg. Save the rest for an egg wash. For cookies and muffins, rounding to the nearest whole egg is usually fine. For cakes and custards, be more precise. When doubling, just double the eggs.
In Tradish (launching soon), you can tap servings up or down on any recipe to double or halve the ingredient amounts. It's temporary, just for that cook, so your saved recipe stays exactly as it was. It does not rewrite the steps or cook times, which is on purpose: those depend on your pan and your oven, and that's the part you'll adjust yourself using the steps below.
This is the step most people skip, and it's the one that ruins the most doubled recipes.
Doubled batter in the same pan gets twice as deep, so the edges overbake while the center stays raw. Halved batter in the original pan spreads thin and dries out.
The fix is to match the surface area, not just the volume. Some handy numbers (length times width for rectangles, and roughly 3.14 times the radius squared for rounds):
So a doubled 8x8 recipe (about 128 square inches) fits nicely in a 9x13. A doubled 9x13 recipe fits on a half sheet pan, or split it between two 9x13s. A halved 9x13 recipe fits well in an 8x8 or 9-inch round.
If you can't match the pan, make two batches in two original-size pans.
If you kept the batter at the same depth (Step 3), the baking time will often be close to the original. Not identical, but close. Start checking a few minutes before the original time and keep going from there.
If the batter ends up deeper than the original:
Halved into a smaller pan? Start checking early.
Doneness cues matter more than minutes when scaling:
Cookies are the friendliest thing to scale: each cookie is the same size, so bake time per tray stays about the same. You just bake more trays.
Tradish is launching on iOS and Android soon. Scale servings up or down for tonight's cook without ever touching your saved recipe. Join the waitlist for early access and our best launch price.
Soups, stews, and sauces. A doubled batch in a deeper pot reduces more slowly, so it can taste thin. Hold back some liquid at first and add it as needed. When halving, the reverse happens: more evaporation, so keep extra broth or water nearby.
Browning and searing. If you double the meat and throw it all in one pan, it steams instead of browning. Sear in batches. Same goes for roasting vegetables: spread them across two sheet pans rather than piling them on one.
Boil and simmer times. A bigger pot takes longer to come to a boil. Plan a little extra time.
Baking soda, baking powder, and yeast are the ingredients most likely to misbehave when scaled.
For a simple double, multiplying leavening by two usually works in cookies, muffins, and pancakes. For cakes, and especially when tripling, many bakers use a little less than the full multiple, since too much can make a cake rise, then sink or taste bitter.
A few practical tips:
The first time you scale a recipe, it's an experiment. The second time should be easy. After you cook, jot down:
In Tradish, when you finish cooking, you can add a cook log entry with a 1–5 star rating, a photo, notes, and the date. It's the perfect place for "doubled in a 9x13, took about 10 extra minutes." You can also add notes right on the recipe through the save and organize features.
No. If you use a larger pan so the food stays at the same depth, the time is often close to the original. Deeper or thicker food takes longer, but usually not twice as long. Check for doneness early.
Yes, but it's tricky. Use a pan with roughly double the surface area, and consider slightly less than double the leavening. For the most reliable result, bake two separate batches.
Use 1 whole egg, then beat a second egg and add about half of it (roughly 2 tablespoons for a large egg). For forgiving recipes like cookies or pancakes, rounding to 1 or 2 eggs usually works. For cakes and custards, be precise.
Start with less than double, about one and a half times the original, then taste and adjust. Salt and strong spices can become overpowering in larger batches. You can always add more at the end.
Many recipe apps do. Tradish, launching on iOS and Android soon, lets you tap servings up or down to double or halve ingredients for one cook without changing your saved recipe. You still adjust pan and timing yourself.
Multiply the main ingredients, go easy on salt, spice, and leavening, and match your pan so the depth stays the same. Trust doneness cues over the clock. Write down what worked, and next time you won't have to think.
Tradish is launching on iOS and Android soon. Join the waitlist to be first to know when we launch.
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