The sweet spot: 20 to 50 g of net carbs
On a ketogenic diet, you typically aim for 20 to 50 grams of net carbs per day. This threshold allows your body to switch into ketosis, meaning it burns fat as its primary fuel instead of glucose. Most beginners start at 20 g to get into ketosis quickly, then adjust based on how their body responds.
Net carbs vs total carbs
This is a key distinction. Net carbs equal total carbs minus fiber. Fiber passes through your system undigested and does not affect blood sugar. For example, 100 g of broccoli has about 7 g of total carbs but only 3.5 g of net carbs thanks to its fiber content. On keto, net carbs are what you track.
Foods to cut out
The main keto enemies are refined carb-heavy foods: bread, pasta, rice, potatoes, cereal, soda, fruit juice, and sweets. But watch out for sneaky sources too: store-bought sauces, flavored yogurt, tropical fruits like bananas and mangoes, and legumes like lentils and chickpeas are surprisingly carb-heavy.
Foods to load up on
Leafy greens like spinach, arugula, and lettuce are extremely low in net carbs. Then come cauliflower, broccoli, zucchini, mushrooms, and avocados. For fruit, only berries (raspberries, blackberries) work in small amounts. And of course, proteins and fats have zero or near-zero carbs: meat, fish, eggs, butter, olive oil.
How to track your carbs
For the first 2 to 3 weeks, track everything to train your instincts. Read nutrition labels. Weigh your food if needed. Over time you will learn to estimate your carb intake without measuring every gram. The goal is building good food habits, not obsessing over numbers forever.
Hidden carb traps
Even foods that seem keto-friendly can hide carbs: store-bought tomato sauce (often loaded with sugar), bottled salad dressings, cashews (more carbs than macadamias), and milk (12 g of carbs per glass). Stay alert, especially during your first few weeks.
Everyone is different
Some people stay in ketosis at 50 g of net carbs, others need to stay under 20 g. It depends on your metabolism, activity level, and insulin sensitivity. The only way to find your number is to experiment and pay attention to how your body responds.
Let Cetona do the math
Counting carbs by hand gets old fast. Cetona builds your personalized keto plan with macros calculated for you, including the right amount of net carbs for your profile. No more pulling out the calculator before every meal.
For the full picture on this topic, check our complete keto diet guide: the science, macros, food list, 7-day plan and FAQ in one place.