A single large egg white contains 17 calories. Almost all of those calories come from protein, with virtually no fat, no cholesterol, and no carbohydrates to speak of. That makes egg whites one of the leanest protein sources available.
Calories by Serving Size
One large egg white weighs about 33 grams. If you’re cooking with liquid egg whites from a carton or separating multiple eggs, here’s how the calories scale up:
- 1 large egg white (33g): 17 calories, 3.6g protein
- 3 large egg whites (99g): 51 calories, 10.8g protein
- 1/2 cup liquid egg whites (~122g): 63 calories, 13.2g protein
- 1 cup liquid egg whites (~243g): 126 calories, 26.5g protein
- 100 grams: 52 calories
A three-egg-white omelet, for example, gives you nearly 11 grams of protein for roughly 50 calories. That’s a ratio most other foods can’t match.
Why Egg Whites Are So Low in Calories
Egg whites are essentially protein dissolved in water. A single white contains less than 0.08 grams of fat, which is why the calorie count stays so low. For comparison, the yolk of the same egg has 55 calories and 4.9 grams of fat. The yolk also carries 210 milligrams of cholesterol, while the white has none.
Roughly 85% of the calories in an egg white come from protein. That percentage is higher than chicken breast, Greek yogurt, or most protein powders, making egg whites particularly useful if you’re trying to hit a protein target without adding extra calories from fat or carbs.
Egg Whites vs. Whole Eggs
A whole large egg has about 71 calories and 6.3 grams of protein. Swapping in egg whites saves you 54 calories per egg, which adds up quickly in a scramble or baking recipe. But you’re also leaving nutrients on the plate.
The yolk is where most of the egg’s vitamins live. It contains vitamins A, D, E, K, and several B vitamins, along with iron, zinc, and a substantial amount of choline, a nutrient important for brain function and bone health. Yolks are also one of the best dietary sources of lutein, a compound that supports eye health. The white contributes some minerals, including about 54 milligrams of potassium, 6.6 micrograms of selenium, and a small amount of magnesium, but it can’t compete with the yolk’s micronutrient density.
If your goal is purely cutting calories or limiting fat intake, egg whites are the obvious choice. If overall nutrition matters more than calorie counting, whole eggs deliver a more complete package.
Protein Quality in Egg Whites
Egg white protein contains all nine essential amino acids your body can’t produce on its own. It’s especially rich in leucine, the amino acid most directly involved in triggering muscle repair and growth. A single egg white provides 335 milligrams of leucine, along with meaningful amounts of lysine, valine, and isoleucine.
How you cook your egg whites matters more than you might expect. Your body absorbs about 91% of the protein from cooked eggs but only around 51% from raw eggs. So blending raw egg whites into a smoothie wastes nearly half the protein you’re consuming. A quick scramble, microwave, or hard boil makes a real difference in how much of that protein your muscles actually get to use.
Practical Uses for Calorie Control
A common approach is mixing whole eggs with extra whites. Two whole eggs plus two egg whites gives you about 176 calories and nearly 20 grams of protein, keeping the yolk’s vitamins in play while boosting the protein-to-calorie ratio. This works well in scrambles, frittatas, or anywhere you’d normally use eggs.
For baking, substituting two egg whites for one whole egg reduces calories and fat in the final product, though it can change the texture slightly since yolk fat contributes to moisture and richness. In recipes that rely on eggs mainly for binding or leavening, the swap works without much difference. In custards or rich cakes where yolk flavor matters, you’ll notice the change.
Liquid egg whites from a carton are pasteurized, so they’re convenient for measuring exact portions. Most brands match the nutritional profile of fresh whites almost exactly: about 25 calories per quarter cup.