Ketogenic Calculator

Ketogenic diet targets hold net carbs low for ketosis, scale protein to lean body mass, and let fat fill the remaining calorie budget. Body metrics, activity level, and weight goal feed the Mifflin-St Jeor equation for Basal Metabolic Rate (BMR) and an activity multiplier for Total Daily Energy Expenditure (TDEE). Once a calorie deficit or surplus is applied, protein grams are set from lean mass, net carbs are subtracted as a fixed amount, and the remaining energy goes to fat. This keto-specific approach differs from general macro tools, which distribute protein, carbs, and fat through percentage presets instead.

• Sex adjusts the BMR formula by +5 for males and -161 for females.
• Height and weight accept decimals or fractions, such as 5.5 or 5 1/2.
• Age lowers BMR over time.
• Body fat percentage, estimated visually or measured with calipers when the exact figure is unknown, drives the lean body mass figure that sets the protein target.
• Activity level ranges from Sedentary (1.2) to Very Active (1.725), with a Custom option for entering a specific multiplier.
• A goal of Lose, Maintain, or Gain applies a deficit or surplus percentage to the calorie target.
• Net carbs per day defaults to the standard keto recommendation of 20g or fewer for steady ketosis.
• Protein ratio, in grams per pound of lean body mass, scales with activity level.

Settings holds a step-by-step view showing BMR, TDEE, and macro derivations with the entered values substituted in.

Mifflin-St Jeor BMR for males: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age + 5. For females: subtract 161 instead of adding 5. TDEE = BMR x activity multiplier. Protein (g) = lean body mass (lbs) x protein ratio. Fat (g) = (target calories - protein calories - carb calories) / 9.

A ketogenic calculator adapts protein, fat, and net carb targets to body composition and weight goal, whether for a first entry into ketosis or for tuning macros around training, while keeping net carbs anchored at a ketosis-friendly level throughout.

• Weight Loss: A calorie deficit of 10 to 20 percent creates a sustainable keto plan; the entered body fat percentage helps protect lean mass while maximizing fat burn.
• Muscle Building: A 5 to 10 percent calorie surplus with a protein ratio of 1.0 to 1.2 g per pound of lean mass supports hypertrophy while staying in ketosis.
• Athletic Performance: The Moderately Active or Very Active setting matches training volume, and net carbs can rise toward the upper keto limit under a targeted or cyclical protocol.
• Health Management: The Maintain Weight goal establishes a steady nutritional framework anchored to lean body mass.
• Meal Planning: Daily fat, protein, and net carb outputs divide across meals to build keto-friendly grocery lists and weekly portion guides.
• Progress Tracking: Targets recalculate as weight and body fat shift, keeping them aligned with the current physique.
• Education: The step-by-step view shows exactly how BMR, TDEE, and macro allocation derive from the entered inputs.

This tool is intended for informational and educational purposes only. It does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for any health-related concerns or decisions.