Macro Calculator
Your Estimated Daily Needs
2,450 kcal/day
Protein
180g
Carbs
250g
Fat
80g
| Basal Metabolic Rate (BMR) | |
|---|---|
| Total Daily Energy Expenditure (TDEE) | |
| Target Calories for Goal | |
| Protein (grams) | |
| Carbohydrates (grams) | |
| Fat (grams) |
Scenarios
Save your results to compare different goals like "Cutting" or "Bulking".
What Are Macros and Why Track Them?
Macronutrients, or "macros," are the three core components of any diet: protein, carbohydrates, and fat. Unlike micronutrients (vitamins and minerals), your body needs these in large amounts to function. Each macro provides energy (calories) and plays a vital role in your health.
- Protein (4 calories per gram): The building block of the body. It's essential for muscle repair and growth, hormone production, and immune function.
- Carbohydrates (4 calories per gram): The body's primary source of energy. They fuel your brain, kidneys, heart muscles, and central nervous system.
- Fat (9 calories per gram): Crucial for brain health, absorbing fat-soluble vitamins (A, D, E, K), producing hormones, and providing a dense source of energy.
Tracking macros instead of just calories allows for a more strategic approach to nutrition. By controlling the ratio of these nutrients, you can better optimize your diet to achieve specific goals, whether it's losing fat, building muscle, or improving athletic performance.
How to Calculate Calories and Macros (Formulas Explained)
This calculator automates a multi-step process to give you a personalized recommendation. Here’s a breakdown of the science behind it:
- Basal Metabolic Rate (BMR): We first calculate your BMR using the Mifflin-St Jeor equation, which is considered one of the most accurate formulas. It estimates the calories your body burns at complete rest:
- For men: BMR = 10 * weight (kg) + 6.25 * height (cm) - 5 * age (y) + 5
- For women: BMR = 10 * weight (kg) + 6.25 * height (cm) - 5 * age (y) - 161
- Total Daily Energy Expenditure (TDEE): Your BMR is just the baseline. We then multiply it by an activity factor to find your TDEE—the total calories you burn in a day, including exercise. The more active you are, the higher your TDEE.
- Goal Adjustment: To lose or gain weight, you must create a calorie deficit or surplus. The calculator adjusts your TDEE based on your goal, typically by adding or subtracting 500 calories, which corresponds to roughly 1 lb (0.5 kg) of weight change per week.
- Macro Split: Finally, the total target calories are divided among protein, carbs, and fat based on common, effective ratios. Protein is often set based on body weight to support muscle mass, fat is set as a percentage of total calories for hormonal health, and carbs fill the remaining calorie budget.
Adjusting Macros for Weight Loss vs. Muscle Gain
Your goals significantly change your ideal macro split. While the calorie target is the most important factor, adjusting nutrient ratios can optimize your results.
- For Weight Loss: A higher protein intake is crucial. It helps preserve muscle mass while you're in a calorie deficit, and its high thermic effect of food (TEF) means your body burns more calories digesting it. Protein also increases satiety, helping you feel fuller for longer.
- For Muscle Gain: A caloric surplus is necessary. Protein remains high to provide the building blocks for new muscle tissue. Adequate carbohydrates are also vital to fuel intense workouts and replenish glycogen stores, while sufficient fat supports hormone production, including testosterone.
Protein, Carbs, and Fats — Optimal Ratios
There is no single "perfect" macro ratio; it depends on your goals, body type, and preferences. However, some general guidelines are:
- Protein: A common recommendation is 1.6-2.2 grams per kilogram of body weight (or about 0.7-1.0 g/lb). Athletes or those in a steep calorie deficit may benefit from the higher end of this range.
- Fat: Generally, 20-30% of your total daily calories should come from healthy fats. Going too low can negatively impact hormone levels and overall health.
- Carbohydrates: After setting protein and fat, carbohydrates make up the rest of your calorie allowance. Their amount can be manipulated to control energy levels and support performance.
Frequently Asked Questions
Here are answers to common questions about macronutrient tracking.
- What are macros in nutrition?
- Macros, short for macronutrients, are the three primary nutrients that your body needs in large amounts to function correctly: protein, carbohydrates, and fat. Each provides energy in the form of calories and serves specific roles in the body.
- How does this calculator work?
- This calculator uses the Mifflin-St Jeor formula to estimate your Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest. It then multiplies your BMR by an activity factor to determine your Total Daily Energy Expenditure (TDEE). Finally, it adjusts your TDEE based on your fitness goal (weight loss, maintenance, or gain) and splits the resulting calorie target into protein, carbohydrate, and fat ratios.
- Can I use this for weight loss?
- Yes. To lose weight, you need to be in a caloric deficit, meaning you consume fewer calories than your body burns. Select the 'Lose Weight' goal, and the calculator will subtract a set number of calories (typically 500) from your daily maintenance calories (TDEE) to create a sustainable deficit.
- Can I use this for muscle gain?
- Absolutely. To gain muscle, you need a caloric surplus to fuel muscle growth and repair. Select the 'Gain Weight' goal, and the calculator will add a set number of calories (typically 500) to your TDEE. Ensure you are also engaging in regular resistance training to promote muscle synthesis.
- Is the calculator accurate?
- This calculator provides a scientifically-based estimate and is a great starting point. However, individual metabolisms can vary. The best approach is to use these numbers as a baseline, track your progress for 2-4 weeks, and adjust your intake based on your actual results.
- How often should I recalculate my macros?
- It's a good idea to recalculate your macros every 4-6 weeks or after a significant change in your body weight (e.g., losing or gaining 5-10 lbs/2-5 kg), activity level, or fitness goals. This ensures your targets remain aligned with your body's current needs.
Disclaimer: This calculator provides estimates for informational purposes only. It is not a substitute for professional medical advice. Consult a doctor, registered dietitian, or certified nutritionist for personalized advice regarding your health and nutrition.
