QUICK ANSWER
How many calories are in natto?
For natto, the locked generic natto record provides 211 kcal per 100 g; use only a matching state and source-held weight.
211 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
Natto 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
- 211 kcal
- Protein
- 19.4 g
- Carbohydrate
- 12.7 g
- Fat
- 11 g
- Fibre
- 5.4 g
- Sodium
- 7 mg
- Potassium
- 729 mg
- Magnesium
- 115 mg
Source: USDA FoodData Central SR Legacy record 172443. 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
Protein
19.4 g per 100 g. From Natto.
Carbohydrate
12.7 g per 100 g. From Natto.
Fat
11 g per 100 g. From Natto.
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 natto fits in a varied eating pattern.
Sodium
7 mg per 100 g in the selected USDA record.
Potassium
729 mg per 100 g in the selected USDA record.
Magnesium
115 mg per 100 g in the selected USDA record.
Phosphorus
174 mg per 100 g in the selected USDA record.
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.
generic natto
Selected nutrition reference.
seasoned natto
Use its own matching record or product label.
soybeans
Keep this state separate from the selected reference.
mixed rice bowl
Use the complete product label or recipe.
PRACTICAL CONTEXT
How natto 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.
Portion basis
The page scales only source-held weights from 211 kcal per 100 g.
Fibre check
The selected record lists 5.4 g fibre per 100 g.
Protein check
The selected record lists 19.4 g protein per 100 g.
Best logging move
Match generic natto exactly and keep seasoned natto separate.
QUALITY & SAFETY
How to choose, store and prepare it
Store
Store the unopened product according to package directions.
After opening or cutting
After opening, follow the package directions and keep the container and closure clean.
Prepare
Review the package ingredient and allergen statement for soy.
Safety boundary
This page represents generic natto; the nutrient record does not establish storage duration or clinical advice.
PHOTO LOGGING
How to log natto 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 the exact reference state: Natto.
- 02
Use edible grams. Every named weight is held by the selected local USDA record. The 100 g entry is the source's nutrient basis; no household portion was invented.
- 03
Log oil, sauce, sweetener, salt and recipe ingredients separately.
- 04
Use a separate record when preparation changes the food state.
COMMON QUESTIONS
Natto calorie and nutrition questions
How many calories are in 100 g of natto?
211 kcal in the locked Natto record.
Which state does this natto page use?
Natto. State and processing are part of the answer.
How much fibre is in natto?
5.4 g per 100 g in the selected record.
Is seasoned natto included?
No. seasoned natto needs its own matching record or product label.
Where do the portion weights come from?
Named weights come from the selected local USDA record; the 100 g entry is the source nutrient basis.
KEEP EXPLORING
Related food guides
SOURCES & METHOD
Where these numbers come from
Natto, per 100 g edible portion. Numeric nutrition and named portion claims use the locked local USDA record. No household portion, search demand, storage duration, clinical effect or medical advice is inferred.
Open USDA FoodData Central SR Legacy record 172443 ↗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.