Health and fitness tools
Macro Calculator
Estimate daily calorie and macronutrient targets from your body stats, activity level, and goal locally in your browser.
Plan your daily protein, carbs, and fat targets.
Enter your age, sex, height, weight, activity level, and weight goal to estimate your basal metabolic rate, total daily energy expenditure, and a calorie target adjusted for your goal. Choose a macro ratio to see daily gram targets for protein, carbohydrates, and fat. This is a general planning estimate based on the Mifflin–St Jeor equation and common activity factors, not medical or nutritional advice; your values are calculated locally and are not uploaded or stored.
Frequently Asked Questions
Everything you need to know about this tool, how it works, and privacy.
How does the macro calculator work?
The calculator estimates your basal metabolic rate (BMR) using the Mifflin–St Jeor equation, then multiplies by an activity factor to get your total daily energy expenditure (TDEE). Your goal adjusts the TDEE up or down (e.g., -500 kcal/day for weight loss). The chosen macro ratio splits the target calories into protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g).
Which activity level should I choose?
Sedentary for little or no exercise, Light for 1–3 days per week, Moderate for 3–5 days per week, Active for 6–7 days per week, and Very active for a physical job or twice-daily training. Be realistic; overestimating activity inflates calorie targets.
What do the macro ratio presets mean?
Balanced is 30% protein, 40% carbs, 30% fat. High protein is 40% protein, 30% carbs, 30% fat. Lower carb is 35% protein, 25% carbs, 40% fat. Lower fat is 30% protein, 50% carbs, 20% fat. Choose the one that fits your dietary preference.
Is this a meal plan or medical advice?
No. This is a general planning estimate based on common formulas and assumptions. Individual needs vary with body composition, health conditions, medications, and genetics. Consult a registered dietitian or qualified healthcare professional for personalized nutrition advice.
Do my values stay private?
Yes. All calculations run locally in your browser. CodeASystem does not upload or store the values you enter.