TDEE Calculator for Keto: How Many Calories Do You Need on Low Carb?
The ketogenic diet restricts carbohydrates to under 50g per day to induce ketosis. But calories still determine whether you lose, maintain, or gain weight. Your TDEE is the starting point: eat below it to lose weight, at it to maintain, or above it to gain. Many keto beginners over-eat fat calories without realising it — knowing your TDEE prevents this.
The ketogenic diet flips the standard macronutrient ratio on its head. Instead of carbohydrates as your primary fuel, you rely almost entirely on fat, with carbs restricted to 20 to 50 grams per day. This forces your body into ketosis, where it burns fat for fuel instead of glucose. Your TDEE doesn't change on keto, but how you distribute your calories does. A typical keto split is 70 to 75 percent fat, 20 to 25 percent protein, and 5 to 10 percent carbohydrates. The first one to two weeks often involve a drop of 1 to 3 kg on the scale, which is mostly water since each gram of stored glycogen holds about 3 grams of water. Don't mistake this for fat loss. Real fat loss follows the same calorie deficit rules as any other diet.
- Your TDEE stays the same on keto. You still need a calorie deficit to lose weight. Keto is a macronutrient strategy, not a magic shortcut.
- Keep carbs below 20 to 50 grams per day to stay in ketosis. Track net carbs by subtracting fiber from total carbohydrates.
- Increase your sodium, potassium, and magnesium intake. Keto increases electrolyte excretion, which causes the headaches and fatigue known as keto flu.
- Give your body at least 2 to 4 weeks to adapt before judging performance. Energy levels during workouts typically dip initially but recover for most people.
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