Eggs are the ingredient most likely to be measured "by count" in a recipe, and the one where count is least reliable. A recipe written for large eggs quietly assumes about 50 g each, shell included. If your carton says medium or jumbo, every cake, custard and meringue you make with it is a slightly different recipe. This guide gives you the weights, the conversions and the rules of thumb that let you swap egg sizes without guessing.
Egg size classes: what the labels actually mean
In the United States, egg sizes are defined by minimum weight per dozen, not by any single egg. The grades that matter for baking are:
- Medium: about 49 g per egg.
- Large: about 50 g per egg — the default in American baking recipes.
- Extra-large: about 56 g per egg.
- Jumbo: about 63 g per egg.
Outside the US, the scale is similar but the numbers differ: UK medium eggs are about 53 g, and Australian eggs use their own bands. The practical rule is the same everywhere — check the weight printed on the carton, not the colour or the name of the size.
What a large egg weighs, part by part
For recipes that separate eggs, you need the parts, not the whole. A typical US large egg breaks down like this:
- Whole egg, shell on: about 50 g.
- White: about 30 g (about two-thirds of the liquid).
- Yolk: about 18 g (about one-third of the liquid, plus all of the fat).
- Shell: the remaining 2 g or so.
Memorise the 50 / 30 / 18 split and almost every egg question becomes arithmetic. Need four egg whites for a pavlova? That is roughly 120 g. A recipe wants two yolks for custard? About 36 g.
How many eggs in a cup?
Recipes occasionally ask for "half a cup of beaten egg" or "1 cup egg whites". With the numbers above, the conversions are simple:
- 1 cup of beaten whole egg: about 4 large eggs (200 g).
- 1 cup of egg whites: about 8 large whites (240 g).
- 1 cup of yolks: about 11 large yolks (200 g).
- 1 tablespoon of beaten egg: about one-fifth of a large egg.
If a recipe calls for an odd phrase like "3 eggs, lightly beaten" and you are scaling it up, measure the beaten volume instead of counting: three large eggs give about 150 ml. That is a more stable target than three eggs from a jumbo carton, which give closer to 185 ml.
Swapping sizes: when it matters and when it does not
A single egg in a 12-muffin batch can shrug off a size difference — jumbo instead of large adds about 13 g of liquid across a whole batch, usually invisible. But in a genoise, an angel food cake or a creme brulee, eggs are the structure and the liquid. There, a 25% jump in egg weight changes the batter visibly.
The safe swap: weigh the eggs you have, then adjust. If your recipe wants 3 large eggs (150 g total) and you only have medium ones (about 147 g for three), the difference is trivial — use three. If you have jumbo eggs (about 189 g for three), beat them and remove about 39 g of beaten egg before adding the rest. In practice, recipes with 2 or fewer eggs tolerate almost any size; recipes with 4 or more deserve the 50 g-per-egg check.
Egg whites and yolks: the ratio that keeps recipes honest
Every egg-white-based bake (meringues, macarons, chiffon cakes) and every yolk-heavy bake (custards, creme brulee, some cookies) depends on the white-to-yolk ratio staying in balance. When you scale a recipe by whole eggs, the ratio follows along automatically. When you scale by "4 whites" or "3 yolks", use the grams: 120 g whites and 54 g yolks. Our weight converter handles the gram-to-ounce side of this instantly, and the recipe scaler rescales the whole list while keeping the ratio intact.
Room temperature matters more than size
Cold eggs do not whip as high and do not emulsify as readily. Most recipes that call for room-temperature eggs are asking because the batter needs the yolks and whites at about 20 C for maximum volume. Pull eggs from the fridge 30 minutes before baking, or put them in a bowl of warm water for 5 minutes. Weigh them at room temperature too; a cold egg carries a little condensed moisture on the shell that can skew a precise weight.
Substitutions, honestly
Flax or aquafaba swaps work in some recipes, but they change texture and structure, and the conversions are not interchangeable with egg weight. If a recipe is egg-forward (meringue, custard, sponge), there is no drop-in substitute that behaves like a real egg. For binding roles in cookies or quick breads, a quarter cup of unsweetened applesauce or a tablespoon of ground flax mixed with three tablespoons of water replaces one egg by function, not by weight — the recipe is a different bake, and that is fine as long as you expect it.
Bookmark the numbers above, and the next time a carton surprises you, you will already know how many grams are in your mixing bowl.