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  3. /Keto Calculator

Keto Calculator

Free keto calculator: enter your body stats, activity level and goal to get a calorie target plus daily net-carb, protein and fat grams for standard keto.

The ketogenic diet is a very low-carbohydrate, high-fat eating pattern that shifts your body into ketosis, where it burns fat for fuel instead of glucose. A standard keto diet typically provides about 70-75% of calories from fat, 15-20% from protein, and only 5-10% from carbohydrates.

This keto calculator sets your daily targets in grams: net carbohydrates, protein, and fat. It starts from your total daily energy expenditure (TDEE) using the Mifflin-St Jeor equation, then applies your goal — lose, maintain, or gain. Protein is based on your estimated lean body mass, which is calculated from your height, weight, and sex with the validated Boer formula.

Net carbs mean total carbs minus dietary fiber, because fiber does not raise blood sugar. Most people use 20-50 g of net carbs per day; 20 g is a strict starting point, while 50 g is more flexible.

Enter your details and pick your carbs and protein preference — the calculator returns your daily calorie, carb, protein, and fat targets instantly.

30 years
1880
170 cm
120220
70 kg
30200
Net carbs = total carbs - fiber. 20 g is strict keto; 50 g is more flexible.
Grams of protein per kg of lean body mass (LBM is estimated with the Boer formula). 1.2-1.8 g/kg is the common keto range.
Example
Example: ≈2,000 kcal Keto Day

A classic keto day at about 2,000 kcal looks like: 25 g net carbs, 100 g protein, and 167 g fat:

Carbs = 25 x 4 = 100 kcal (5%)
Protein = 100 x 4 = 400 kcal (20%)
Fat = 167 x 9 = 1,503 kcal (75%)

With the calculator, a 30-year-old man, 175 cm, 80 kg, moderately active, losing weight: BMR ≈ 1,749 kcal, TDEE ≈ 2,711 kcal, target ≈ 2,169 kcal. At 20 g net carbs and 1.5 g/kg protein (LBM ≈ 60 kg), the targets are ~20 g carbs, ~90 g protein, and ~192 g fat.

Key Insight: Fat is the flexible remainder — if you raise carbs or protein, fat grams drop automatically to keep your calorie target.

Frequently Asked Questions

What is the ketogenic diet?

It is a very low-carb, high-fat diet (about 70-75% fat, 15-20% protein, 5-10% carbs) that shifts the body into ketosis, where it burns fat for energy instead of glucose.

How many carbs can I eat on keto?

Most people stay within 20-50 g of net carbs per day. 20 g is a strict starting point for reliable ketosis; 50 g is more flexible and still low enough for many people.

What are net carbs?

Net carbs = total carbs - dietary fiber (and often sugar alcohols), because fiber is not digested into glucose. Read labels and subtract the fiber to get your net count.

How much protein should I eat on keto?

Protein is based on lean body mass, about 1.2-1.8 g per kg. Too little can cause muscle loss; too much can slow ketosis in sensitive people. The calculator uses 1.5 g/kg by default.

What is the keto flu and how do I avoid it?

In the first 1-2 weeks you may feel tired or headachy as your body adapts. Drink water, add salt and electrolytes, and ease into carb restriction gradually.

Is keto safe for everyone?

No. It is a clinical treatment for epilepsy and should be supervised for diabetes, kidney disease, pregnancy, or breastfeeding. Consult your doctor before starting; this calculator is not medical advice.

Ketosis and keto-adapted training have real physiological effects, and this calculator provides estimates for educational purposes only — not medical advice. The keto diet is used clinically for epilepsy and may affect blood sugar and medication needs in diabetes; pregnant or breastfeeding women and people with medical conditions should consult their doctor before starting. Expect an adaptation phase (the keto flu) in the first 1-2 weeks.

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