How to Halve a Recipe With One Egg

You found a small-batch recipe online, but you want it smaller. The recipe makes 12 cookies. You only want 6. The math is easy: cut everything in half. Then you get to the eggs. There is one. Now what?

The three ways to halve an egg

1. By weight (most accurate)

Crack the egg into a bowl. Whisk until smooth. Place the bowl on a kitchen scale, hit tare, and pour out 25 grams. This is the method professional bakers use because it removes all the guessing.

2. By volume (no scale needed)

Crack and whisk the same way. Use a tablespoon measure to scoop 2 tablespoons. A large beaten egg measures about 4 tablespoons total, so 2 tablespoons is right at half.

3. The yolk-and-white split (for custards)

For custards and creams, some bakers use one whole yolk in place of half an egg. The yolk gives richness and binding. Skip the white. This is a baker's shortcut, not a universal swap; it works for crème brûlée, custard, and curd.

What to do with the other half

Cover the remaining whisked egg and refrigerate. It keeps for up to 2 days. Use it in:

• Tomorrow's scrambled eggs or omelette (just whisk into more eggs)
• A small batch of pancakes
• An egg wash for bread or pastry (mix with a splash of water)
• French toast batter

When the egg ratio really matters

Eggs do four jobs in baking: they bind, they leaven, they add moisture, and they emulsify. The more a recipe depends on egg structure, the more accuracy matters.

• Cookies and quick breads: eyeballing half an egg is fine.
• Pound cakes and butter cakes: weigh it.
• Sponge cakes, soufflés, and meringues: do not halve. Make the full recipe or scale to a different yolk-to-white ratio entirely.

What about extra-large or jumbo eggs?

US large eggs are 50 grams out of the shell. Extra-large are 56 grams. Jumbo are 63 grams. If your recipe says "large egg" and you only have jumbo, weighing avoids the mismatch. For halving, use 25 grams regardless of egg size.