Keto Macro
Calculator

Understanding Your Keto Macro Targets

The ketogenic diet works by drastically reducing carbohydrate intake so the body switches its primary fuel source from glucose to ketones — molecules produced when the liver breaks down fat. This metabolic state, called nutritional ketosis, is what gives the ketogenic diet its name and its distinct effects. To achieve and maintain ketosis, the typical target is under 20–50 grams of net carbohydrates per day, with the remainder of calories coming from fat (the majority) and protein (moderate amounts).

How Your Calorie Target Is Calculated

This calculator uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for estimating Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest. That BMR is then multiplied by your activity factor to produce your Total Daily Energy Expenditure (TDEE). From there, a caloric deficit or surplus is applied depending on your goal. The macro split is then calculated as percentages of those total calories, with fat providing 9 calories per gram and protein and carbohydrates each providing 4 calories per gram.

Why Fat Is So High on Keto

The high fat percentage is the aspect of keto that surprises people most. On a standard keto protocol, fat makes up 70% of daily calories. Because fat contains 9 cal/g (more than double the density of protein or carbs), this translates to a large number of grams that feels like a lot to eat. In practice, healthy fat sources like avocado, olive oil, nuts, eggs, and fatty fish make it easier to hit this target than loading up on processed saturated fats. The fat serves as the primary fuel source replacing the carbohydrates you’ve removed.

It’s worth understanding that on keto, fat intake is a target to reach — not just a limit. Many beginners under-eat fat while cutting carbs, which leaves them in an energy deficit that causes fatigue and hunger. Eating enough fat is as important as limiting carbs.

Protein: The Most Important Number to Get Right

Protein on keto needs to be moderate — enough to preserve muscle mass, but not so high that excess protein is converted to glucose through a process called gluconeogenesis, which could knock you out of ketosis. The standard keto protein range is 0.6–1.0g per pound of lean body mass (roughly 1.3–2.2g per kilogram). The high-protein keto protocol in this calculator is designed for people who are actively strength training and need higher protein to support muscle retention and growth.

Net Carbs vs Total Carbs

The carb target shown is in net carbs — total carbohydrates minus dietary fibre. Fibre is a carbohydrate that is not digested or absorbed into the bloodstream, so it does not raise blood sugar or insulin and does not contribute to breaking ketosis. This is why high-fibre vegetables like broccoli, spinach, and cauliflower are staples of the keto diet despite containing carbohydrates — their net carb count after subtracting fibre is very low. Always check net carbs, not total carbs, when tracking on keto.