How to use this calculator
Enter your age, gender, weight, and height. Select your activity level honestly. Most people overestimate their activity. If you have a desk job and exercise 3 times per week, choose lightly active or moderately active.
Then select your goal. The calculator automatically applies the optimal macro split: higher protein for weight loss (to preserve muscle), balanced for maintenance, and higher carbs for muscle building (to fuel training). Results show grams, calories, and percentages for each macronutrient.
Understanding the macro splits
Weight loss (40% protein, 30% carbs, 30% fat): Higher protein preserves lean muscle during a calorie deficit, increases satiety between meals, and has a higher thermic effect so your body burns more calories just digesting it.
Maintenance (30% protein, 40% carbs, 30% fat): A balanced approach that provides ample carbohydrates for daily energy and exercise performance while still meeting protein needs for tissue repair.
Muscle building (30% protein, 45% carbs, 25% fat): Higher carbs fuel intense training sessions, replenish glycogen stores, and create an anabolic environment. The caloric surplus of 300 calories supports muscle growth without excessive fat gain.
Frequently asked questions
What are macros and why do they matter?
Macros (macronutrients) are protein, carbohydrates, and fat. Each provides calories and serves different functions in the body. Tracking macros gives you more control over body composition and energy than counting calories alone.
What is the best macro ratio for weight loss?
A split of 40% protein, 30% carbs, and 30% fat works well for most people trying to lose weight. The higher protein intake preserves muscle, keeps you satisfied, and has a higher thermic effect. The key is maintaining a consistent calorie deficit.
How many grams of protein do I need per day?
Active individuals typically need 0.7 to 1.0 grams of protein per pound of body weight. People who lift weights or are in a calorie deficit benefit from the higher end. Sedentary adults can aim for 0.5 to 0.7 grams per pound.
How do I calculate calories from macros?
Protein and carbohydrates each provide 4 calories per gram, while fat provides 9 calories per gram. Multiply grams of each macro by its calorie value, then add them together to get your total daily calories.
Should I adjust macros on rest days?
For most people, keeping macros consistent every day produces similar results and is much simpler to track. Advanced athletes may benefit from eating more carbs on training days and fewer on rest days, but beginners should focus on daily consistency first.