Keto Macro Calculator
Daily fat, protein and carb grams for a ketogenic diet.
Daily fat
156 g
70% of calories
Carbs
25 g
Protein
125 g
Fat
156 g
- Fat51%
- Protein41%
- Carbs8%
On a 2,000-kcal keto day you'd eat about 156g fat, 125g protein and 25g carbs — roughly 70% / 25% / 5% of calories.
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How the Keto Macro Calculator works
The Keto Macro Calculator determines your personalized daily fat, protein, and carbohydrate gram targets so you can enter and sustain ketosis on a ketogenic diet. It's built for anyone transitioning to low-carb eating, optimizing body composition, or managing metabolic health through dietary fat as their primary fuel source.
The calculator begins by estimating your Total Daily Energy Expenditure (TDEE), which combines your Basal Metabolic Rate (BMR) — the calories your body burns at complete rest — with an activity multiplier based on your lifestyle, from sedentary desk work to intense daily training. BMR is calculated using the Mifflin-St Jeor equation, the most clinically validated formula for most adults, using your age, sex, height, and weight. Once TDEE is established, a caloric goal is set by applying your chosen deficit (for fat loss), surplus (for muscle gain), or maintenance level.
With your caloric target set, the calculator distributes those calories across the three macronutrients according to classic ketogenic diet ratios. Carbohydrates are capped at 5–10% of total calories — typically 20–50 grams per day — which is the threshold most people need to suppress insulin sufficiently and shift their liver into producing ketone bodies. Protein is assigned next, usually 20–35% of calories, calculated at roughly 0.7–1.0 grams per pound of lean body mass to preserve muscle without exceeding the amount that could trigger gluconeogenesis and knock you out of ketosis. The remaining calories — often 60–75% of the total — are allocated to dietary fat, the cornerstone fuel of a ketogenic diet.
Lean body mass is the most important factor influencing your protein and fat targets, which is why many versions of the calculator ask for body fat percentage rather than relying solely on total weight. A 180-pound person at 30% body fat has roughly 126 pounds of lean mass and needs significantly less protein than the same weight person at 15% body fat. If you don't know your body fat percentage, the calculator uses population-average estimates based on age, sex, and BMI as a reasonable proxy, though DEXA scans or bioelectrical impedance measurements give the most accurate inputs.
A common mistake users make is treating the carb ceiling as a fixed 20g rule regardless of their individual metabolic context. In reality, some people — particularly those who are highly active or metabolically flexible — can sustain ketosis at 40–50g of net carbs per day, while others with insulin resistance may need to stay under 20g total. Similarly, over-consuming protein is a frequently overlooked error on a ketogenic diet; excess amino acids are converted to glucose via gluconeogenesis, which can blunt ketone production. Use the calculator's outputs as a starting framework, then track your ketone levels with a blood or breath meter to fine-tune your personal carb and protein thresholds.
Formula
Keto: ~70% fat, 25% protein, 5% carbs
Pro tips
- Track net carbs, not total carbs — subtracting fiber gives you a more accurate picture of your glucose load and helps you stay in ketosis without unnecessarily restricting fibrous vegetables.
- Prioritize whole-food fat sources like avocados, olive oil, fatty fish, and nuts; meeting a high fat macro target through ultra-processed foods can undermine the metabolic and inflammatory benefits of a ketogenic diet.
- Increase your sodium, potassium, and magnesium intake deliberately during the first two weeks — carb restriction causes rapid water and electrolyte loss that drives 'keto flu' symptoms, not the diet itself.
- Re-run the calculator every 10–15 pounds of weight change or if your activity level shifts significantly; your TDEE — and therefore your fat and protein gram targets — changes meaningfully as body composition improves.
- If fat loss stalls after 3–4 weeks, audit your fat intake rather than automatically cutting calories further; since fat is calorie-dense at 9 kcal/g, even small measurement errors in cooking oils or nuts can create a substantial hidden surplus.
Key terms
- Ketosis
- — A metabolic state in which the liver produces ketone bodies from fat because carbohydrate intake is too low to sustain glucose as the primary fuel.
- Macros (Macronutrients)
- — The three energy-providing nutrients — fat, protein, and carbohydrates — expressed in grams per day and used to structure a ketogenic diet plan.
- Net Carbs
- — Total carbohydrate grams minus fiber grams (and sometimes sugar alcohols), representing the carbs that actually raise blood glucose and affect ketosis.
- Total Daily Energy Expenditure (TDEE)
- — The total number of calories your body burns in a day, combining resting metabolism with energy used during physical activity.
- Lean Body Mass (LBM)
- — Your total body weight minus fat mass, used as the basis for protein targets on a ketogenic diet to avoid both muscle loss and excess gluconeogenesis.
- Gluconeogenesis
- — The liver's process of converting non-carbohydrate sources — primarily excess protein — into glucose, which can reduce ketone production if protein intake is too high.
