QUICK ANSWER
How many calories are in hard-boiled egg?
A hard-boiled whole egg contains about 155 calories and 12.6 g of protein per 100 g. One large 50 g egg is therefore about 78 calories before mayonnaise, butter or other ingredients.
155 kcal / 100 gNutrition values describe a reference food state, not every individual item. Variety, water content, preparation and portion weight can change the estimate.
THE NUMBERS
Hard-boiled egg nutrition facts per 100 g
The values below use the reference state shown at the top of this page. Keeping one gram basis makes it easier to compare foods before translating the values to the portion you actually ate.
- Calories
- 155 kcal
- Protein
- 12.6 g
- Carbohydrate
- 1.12 g
- Fat
- 10.6 g
- Fibre
- 0 g
- Cholesterol
- 373 mg
- Potassium
- 126 mg
- Iron
- 1.19 mg
Source: USDA FoodData Central SR Legacy record 173424. Values may be rounded for readability.
SERVING SIZE
Calories by portion and serving weight
Words such as “small,” “medium,” “half” and “one piece” are convenient but imprecise. Grams make the estimate reproducible, particularly when natural foods vary in size.
MACROS
Carbohydrate, protein and fat explained
Carbohydrate
Plain hard-boiled egg contains very little carbohydrate and no fibre.
Protein
Egg provides 12.6 g of protein per 100 g, or about 6.3 g in a 50 g large egg.
Fat
Whole egg contains fat in the yolk. Mayonnaise, butter and frying oil add further fat and calories.
MORE THAN CALORIES
Fibre, vitamins and minerals
One food does not need to provide every nutrient. These are the characteristics most useful for understanding where hard-boiled egg fits in a varied eating pattern.
Choline and B12
Eggs can contribute choline and vitamin B12; exact values depend on the database record.
Iron
The whole cooked egg provides 1.19 mg iron per 100 g.
Cholesterol
This record lists 373 mg per 100 g. Individual medical guidance should come from a qualified clinician.
Fibre
Egg contains no fibre, so fibre comes from foods eaten with it.
FOOD STATE MATTERS
How preparation changes the nutrition estimate
A reliable calorie entry should describe the food you actually ate—not merely a food with a similar name.
Hard-boiled
Boiling without added ingredients keeps the entry straightforward.
Fried
Frying oil or butter changes the final total.
Scrambled
Milk, butter, cheese and cooking fat must be included.
Egg whites
Whites alone have a different protein, fat and calorie profile from whole eggs.
PRACTICAL CONTEXT
How hard-boiled egg can fit different goals
There is no universal “good” or “bad” food. Portion, frequency, the rest of the meal, preferences and individual health needs all matter.
Protein goals
Egg can be a convenient measured protein food.
Fibre goals
Pair it with vegetables, fruit, legumes or whole grains because egg has no fibre.
Calorie planning
Count the number and edible weight, plus mayonnaise or cooking fat.
Meal building
Combine egg with produce and a suitable carbohydrate for a more complete meal.
QUALITY & SAFETY
How to choose, store and prepare it
Cook safely
Use current local food-safety guidance for cooking and handling eggs.
Refrigerate
Keep cooked eggs chilled and follow current local food-safety guidance whenever they have been left unrefrigerated.
After peeling
Store peeled hard-boiled eggs covered in the refrigerator.
Discard
Discard eggs with an off-odour or signs of spoilage.
PHOTO LOGGING
How to log hard-boiled egg more accurately
A food photo can suggest the ingredient, but it cannot always reveal exact weight, hidden oil or preparation details. These checks turn an image guess into a better estimate.
- 01
Match whole egg, egg white, hard-boiled, fried or scrambled to the correct record.
- 02
Use edible grams or the count and size when known.
- 03
Log mayonnaise, butter, cheese and cooking fat separately.
- 04
For egg salad, sandwiches or other mixed dishes, log the complete recipe and your portion.
COMMON QUESTIONS
Hard-boiled egg calorie and nutrition questions
How many calories are in one hard-boiled egg?
One large 50 g egg is about 78 calories.
How much protein is in one egg?
A 50 g large egg is about 6.3 g protein using this record.
Does boiling add calories?
No added energy is introduced by water alone.
Are egg whites the same?
No. Egg-white-only records contain much less fat and fewer calories.
Does mayonnaise count?
Yes. Egg salad should include mayonnaise and all other ingredients.
KEEP EXPLORING
Related food guides
SOURCES & METHOD
Where these numbers come from
Values are for whole chicken egg, cooked hard-boiled, per 100 g edible portion. Raw, fried, poached, scrambled, yolk-only and white-only records are separate.
Open USDA FoodData Central SR Legacy record 173424 ↗Page reviewed 26 August 2026. We show the food state, gram basis and source record so readers can check the estimate instead of treating one number as universally exact.