Is natto keto?
natto is keto only in small portions: it has ~6 g of net carbs per 1/2 cup, against the keto diet's 5 g-per-serving limit.
Net carbs = total − fiber
6 g
per 1/2 cup
These are the carbs that count on keto: total carbs minus fiber.
Because it is a soy-based legume, a standard half-cup serving contains 6.4 g of net carbs, making it best enjoyed in moderation on a strict keto diet.
Nutrition facts for natto
How many carbs are in natto?
natto has ~11 g of carbs and ~6 g of net carbs per 1/2 cup (total carbs minus 4 g of fiber).
Why natto is keto only in small portions?
On keto the goal is to stay under ~5 g of net carbs per serving; natto has 6 g per 1/2 cup (11 g total − 4 g of fiber).
How much natto can I eat on keto?
To stay under 5 g of net carbs, the limit is ~68 g of natto.
Related
Reviewed by the Ketorai team · Last updated: September 18, 2026 · How we assign the verdict
For information only. This does not replace advice from a health professional.
Something off? Let us know.
Search another food