Use in Moderation
Grapefruit
11.20g net carbs per 1/2 fruit
Half a grapefruit lands at 11.2 g net carbs, which eats up a big chunk of a typical 20 to 30 g daily keto budget in one go. Keep it occasional, and stick to a quarter if you really want the taste without blowing your numbers.
Built by Barron Hansen · Last updated July 2026
Nutrition Facts
Fits My Daily Budget?
Set your daily net carb limit to see how one serving fits.
One serving uses 56% of your 20g daily budget.
Plan the rest of your day
Good to Know
Most of those carbs come from natural sugar, so skip the common habit of sprinkling sugar on top, and watch sweetened canned segments or cocktail cups packed in syrup, which can double the count. Ruby Red and Star Ruby tend to taste sweeter than the paler white varieties, while Oro Blanco is milder. If you drink the juice instead, the fiber is gone and the sugar concentrates fast, so a small glass can carry far more carbs than the half fruit listed here.
Is Grapefruit Keto? The Full Answer
Grapefruit contains 11.20g net carbs per 1/2 fruit (13.20g total carbs minus 2.00g fiber). Half a grapefruit lands at 11.2 g net carbs, which eats up a big chunk of a typical 20 to 30 g daily keto budget in one go. Keep it occasional, and stick to a quarter if you really want the taste without blowing your numbers.
On a standard ketogenic diet, most people target 20-25g net carbs per day. A single serving uses 56% of a 20g daily carb limit. Track your portions carefully and account for other carbs in your meals.
Better Keto Swaps
Half a grapefruit runs 11.2 g net carbs, which eats up a big chunk of a strict 20 g daily budget, so here are a few brighter, lower-carb options. Berries are the easy win: a half cup of raspberries lands around 3.3 g net carbs and still gives you that tart, juicy bite. Want something with similar zing? Try a squeeze of fresh lemon or lime over sparkling water, where a couple of wedges add only about 1 g net carbs and almost no sugar. For a fuller, citrus-adjacent snack, half a small avocado comes in near 1.8 g net carbs, and the fat helps it sit better with keto macros than fruit sugar does.
Track Your Ketone Levels
The Keto-Mojo meter is the gold standard for confirming you're actually in ketosis. Know your numbers - don't guess.