How to Use Our Macro Calculator
To get your personalized macro recommendations, simply enter the following information. Our calculator uses the well-regarded Mifflin-St Jeor equation to first determine your baseline calorie needs.
Age: Your age in years. Metabolic rate can change with age.
Gender: Select Male or Female. This is used to calculate your basal metabolic rate (BMR), as body composition and metabolic rates differ between sexes.
Height: Enter your current height.
Weight: Enter your current weight. This is a key factor in determining your total daily energy expenditure (TDEE).
Activity Level: Be honest about your daily activity. This significantly impacts your calorie needs.
Sedentary: Desk job with little to no exercise.
Lightly Active: Light exercise or sports 1-3 days a week.
Moderately Active: Moderate exercise or sports 3-5 days a week.
Very Active: Hard exercise or sports 6-7 days a week.
Extremely Active: Very hard exercise, physical job, or training twice a day.
Your Goal: Select your primary fitness objective. This will adjust your total calories to create the necessary energy balance.
Lose Weight: Creates a calorie deficit (typically a 15-20% reduction from your maintenance calories).
Maintain Weight: Calculates the calories needed to maintain your current weight.
Gain Muscle: Creates a calorie surplus (typically a 15-20% increase) to support muscle growth.
Understanding Your Results
Your results will show two key things: your total daily calorie target and your macronutrient breakdown in grams for protein, carbohydrates, and fats. Think of the calorie target as your total energy budget for the day, and the macros as instructions on how to spend that budget for the best results.
Below is a sample breakdown for someone with a 2,000-calorie target for weight loss. Your numbers will be customized to you.
Here’s what each macronutrient does and why it’s important:
Focusing on hitting your gram targets for each macro—especially protein—is more effective than just counting calories alone. This approach ensures your body gets the right fuel to build muscle, lose fat, and function optimally.
Frequently Asked Questions
What are macronutrients?
Macronutrients are the three main nutrient groups that your body needs in large quantities to produce energy and function correctly: protein, carbohydrates, and fat. Unlike micronutrients (vitamins and minerals), which are needed in smaller amounts, macros are the “big three” that make up the caloric content of your food. Managing the ratio of these nutrients is the foundation of a flexible dieting approach.
How do I track my macros?
Tracking your macros involves logging the food you eat and paying attention to its protein, carb, and fat content.
Use a Tracking App: Apps like MyFitnessPal, Cronometer, or Lose It! make this process simple. You can scan barcodes or search their vast food databases.
Get a Food Scale: For accuracy, especially at the beginning, weighing your food is essential. Estimating portion sizes is often inaccurate. A “medium chicken breast,” for example, can vary in weight by 50% or more.
Plan Ahead: It can be helpful to plan your meals for the day in your tracking app before you eat them. This allows you to see how your choices fit your targets and make adjustments on the fly.
Concrete Example: Tracking a Simple Meal
Let’s say your lunch is 150g of cooked chicken breast, 200g of cooked white rice, and 80g of avocado.
Chicken Breast (150g): ~46g Protein, 0g Carbs, 5g Fat
White Rice (200g): ~5g Protein, 58g Carbs, 1g Fat
Avocado (80g): ~2g Protein, 7g Carbs, 12g Fat
Meal Total: 53g Protein, 65g Carbs, 18g Fat. You would subtract these amounts from your daily macro targets and plan your remaining meals accordingly.
What is a good macro ratio for weight loss?
There is no single “best” ratio, but a common and effective starting point for weight loss is a higher protein intake. A typical split is:
This ratio prioritizes protein to help preserve muscle mass while in a calorie deficit and to increase feelings of fullness, which makes it easier to stick to your diet. Our calculator uses a similar evidence-based ratio for its weight loss setting.
Can I eat whatever I want as long as it fits my macros (IIFYM)?
The concept of “If It Fits Your Macros” (IIFYM) means you can theoretically eat any food as long as the total protein, carbs, and fat fit within your daily targets. While this flexibility is a major benefit, food quality still matters.
For best results, aim to get 80-90% of your macros from whole, nutrient-dense foods (lean meats, vegetables, fruits, whole grains). You can use the remaining 10-20% for more processed “fun” foods. This balanced approach, often called “flexible dieting,” ensures you get enough fiber, vitamins, and minerals for overall health while still enjoying treats, making the diet sustainable long-term.
Why is protein so important for my fitness goals?
Protein is arguably the most critical macronutrient for changing your body composition, whether you’re losing fat or gaining muscle.
For Muscle Gain: Protein provides the amino acids necessary to repair and rebuild muscle fibers that are broken down during exercise, leading to muscle growth (hypertrophy).
For Fat Loss: A high-protein diet helps you feel fuller for longer, reducing overall calorie intake. It also has a higher Thermic Effect of Food (TEF), meaning your body burns more calories digesting it compared to carbs and fats. Most importantly, it helps prevent muscle loss when you are in a calorie deficit.
How often should I recalculate my macros?
You should recalculate your macros whenever your circumstances change significantly. A good rule of thumb is to reassess every 4-6 weeks or after every 5-10 pounds of weight change. Your energy needs will change as you lose or gain weight, and your macro targets should be adjusted to reflect your new body weight and continue driving progress. You should also recalculate if your activity level changes, for example, if you switch from a sedentary job to a more active one.
After calculating your macros, you might be interested in a more detailed look at your health metrics. Use our Body Fat Calculator to estimate your body composition, or see how your calorie needs fit within your overall diet using our basic Calorie Calculator.
