A large hard-boiled egg contains 6.3 g of protein (USDA). Just over half of that is in the white, and the rest in the yolk. Egg protein is the benchmark nutrition scientists score other proteins against, because it contains every essential amino acid in a readily used ratio.
Where these numbers come from
Protein figures are calculated from USDA FoodData Central, “Egg, whole, cooked, hard-boiled” (12.58 g protein per 100 g), scaled to each US egg size. Protein-quality scoring reflects the FAO/WHO methods described below.
What we haven’t done: no registered dietitian or physician has reviewed this page. It reports published data and isn’t advice about your own protein needs — those depend on your body weight, activity and health, and a qualified professional is the right person to ask.
Protein by egg size
| Egg size | Protein | Calories | Protein per 100 kcal |
|---|---|---|---|
| Small | 4.8 g | 59 kcal | 8.1 g |
| Medium | 5.5 g | 68 kcal | 8.1 g |
| Large | 6.3 g | 78 kcal | 8.1 g |
| Extra large | 7.0 g | 87 kcal | 8.1 g |
| Jumbo | 7.8 g | 96 kcal | 8.1 g |
The last column is identical all the way down, which is the point: egg size changes the amount, never the ratio. An egg is an egg regardless of how big it is.
Why egg protein is the reference standard
Protein quality has two components — whether a food contains all nine essential amino acids, and how well your body can actually absorb and use them. Whole egg scores at or near the ceiling on both, which is why it has historically been used as the reference protein that other foods are measured against.
Under PDCAAS, the scoring system the FAO and WHO adopted in 1991, egg protein rates 1.0 — the maximum. The newer DIAAS method, which measures absorption further along the digestive tract, also places whole egg among the highest-scoring foods, above most plant proteins. This is why “complete protein” gets attached to eggs so often: it’s shorthand for containing all nine essential amino acids in usable proportions.
Cooking helps, too. Raw egg white contains avidin, which binds biotin, and its protein is digested markedly less efficiently than cooked. Boiling denatures both problems away — one of the few cases where cooking improves a protein’s nutritional availability rather than diminishing it.
White or yolk?
| Part | Protein | Calories | Fat |
|---|---|---|---|
| White | 3.6 g | 17 kcal | 0 g |
| Yolk | 2.7 g | 55 kcal | 4.5 g |
The white carries slightly more protein for a third of the calories, which is the entire case for egg-white-only eating. The counter-case is that the yolk holds the choline, vitamin D, vitamin A, and lutein — see the full nutrition facts for what that costs you.
Worth noting: some research on muscle protein synthesis has found whole eggs to produce a greater response than an equivalent amount of protein from whites alone, which suggests the yolk contributes something beyond its protein count. The evidence base is still developing, so treat that as an interesting finding rather than settled fact.
How boiled eggs compare
| Food | Protein per 100 g |
|---|---|
| Chicken breast, roasted | ~31 g |
| Greek yogurt, plain non-fat | ~10 g |
| Hard-boiled egg | 12.6 g |
| Cooked lentils | ~9 g |
| Firm tofu | ~17 g |
Eggs sit in the middle by weight — they’re not the densest protein source available. Where they win is quality per calorie, portability, cost, and the fact that six of them cook in eleven minutes and keep a week in the fridge. That combination is why they’re a meal-prep staple.
Getting more protein from boiled eggs
Practical, without straying into advice about your intake: cook a batch of hard boiled eggs at once — the time is the same for one egg or a dozen. Keep them unpeeled in the shell, which is a better container than anything you own. And if you’re using them in egg salad, remember the dressing usually contributes more calories than the eggs do.
Boiled egg protein questions
How much protein is in a boiled egg?
A large hard-boiled egg has 6.3 g of protein, according to USDA FoodData Central. A small egg has about 4.8 g and a jumbo about 7.8 g. The protein-to-calorie ratio stays the same across sizes at roughly 8 g per 100 calories.
How much protein is in two boiled eggs?
About 12.6 g for two large eggs, in around 155 calories. Three large eggs come to roughly 18.9 g of protein.
Is there more protein in the egg white or the yolk?
The white, slightly — 3.6 g versus 2.7 g in a large egg, and for a third of the calories. The yolk holds the fat and most of the vitamins and minerals, so eating whites only trades away choline, vitamin D and vitamin A for a leaner protein source.
Is egg protein better than protein from other foods?
By quality measures, it’s at the top. Whole egg scores 1.0 on PDCAAS, the FAO/WHO scoring system’s maximum, because it contains all nine essential amino acids in proportions the body absorbs well. By weight, chicken breast and tofu contain more protein per 100 g.
Does boiling an egg reduce its protein?
No — it improves how much of it you can use. Raw egg white is digested considerably less efficiently than cooked, and it contains avidin, which binds biotin. Heat resolves both, making a boiled egg a better protein source than a raw one.
Sources
- USDA FoodData Central — Egg, whole, cooked, hard-boiled; Egg, white, raw; Egg, yolk, raw.
- FAO/WHO — Protein Digestibility-Corrected Amino Acid Score (PDCAAS), adopted 1991; and the FAO’s 2013 report introducing DIAAS.
- USDA FoodData Central — comparison foods in the protein table.
Figures last checked against source: August 8, 2026.
A dozen takes the same eleven minutes as one
Batch-cook them, leave them in the shell, and you’ve got a week of protein sorted.