Free Macro Calculator

free macro calculator
Maintenance (Maintain Weight)Weight Loss (Fat Loss)Muscle Gain (Bulking)
MaleFemale
Sedentary (Office job, little exercise)Lightly Active (1-3 days/week)Moderately Active (3-5 days/week)Very Active (6-7 days/week)Extra Active (Physical job + training)
Daily Targets
Calories0 kcal
Protein0 grams
Carbohydrates0 grams
Fats0 grams
function calculateMacros(){var age=parseFloat(document.getElementById('age').value);var weightLbs=parseFloat(document.getElementById('weight').value);var heightFt=parseFloat(document.getElementById('height_ft').value);var heightIn=parseFloat(document.getElementById('height_in').value);var gender=document.getElementById('gender').value;var activity=parseFloat(document.getElementById('activity').value);var goal=document.getElementById('goal_type').value;if(isNaN(age)||isNaN(weightLbs)||isNaN(heightFt)||isNaN(heightIn)){alert('Please fill in all numeric fields correctly.');return;}var weightKg=weightLbs*0.453592;var heightCm=((heightFt*12)+heightIn)*2.54;var bmr;if(gender==='male'){bmr=10*weightKg+6.25*heightCm-5*age+5;}else{bmr=10*weightKg+6.25*heightCm-5*age-161;}var tdee=bmr*activity;var targetCals;if(goal==='lose'){targetCals=tdee-500;}else if(goal==='gain'){targetCals=tdee+500;}else{targetCals=tdee;}var p_cal=targetCals*0.30;var c_cal=targetCals*0.40;var f_cal=targetCals*0.30;var protein=p_cal/4;var carbs=c_cal/4;var fats=f_cal/9;document.getElementById('res_cal').innerHTML=Math.round(targetCals);document.getElementById('res_protein').innerHTML=Math.round(protein);document.getElementById('res_carbs').innerHTML=Math.round(carbs);document.getElementById('res_fats').innerHTML=Math.round(fats);}

Calculator Use

The free macro calculator is a professional-grade tool designed to help you quantify your nutrition. Whether you are looking to shed body fat, maintain your current physique, or build lean muscle mass, understanding your macronutrient ratios is the most effective way to reach your goals.

By calculating your Total Daily Energy Expenditure (TDEE) and applying specific macronutrient splits, this tool provides you with a blueprint for your daily meals. It removes the guesswork from dieting by providing specific targets for protein, carbohydrates, and fats.

Age, Gender, Weight, and Height
These biometric markers are used to calculate your Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest.
Activity Level
This factor accounts for the energy expended during work, exercise, and daily movement. Selecting an accurate activity level is crucial for determining your maintenance calories.
Goal (Weight Loss, Maintenance, Muscle Gain)
Your goal determines the caloric adjustment. A "lose" goal typically creates a 500-calorie deficit, while a "gain" goal adds 500 calories to support muscle protein synthesis.

How It Works

Our free macro calculator utilizes the Mifflin-St Jeor Equation, which is widely considered the gold standard in clinical settings for estimating BMR. Once your BMR is established, the following steps are taken:

TDEE = BMR × Activity Multiplier

  • Protein (30%): Essential for muscle repair and satiety. Contains 4 calories per gram.
  • Carbohydrates (40%): The body's primary energy source for high-intensity training. Contains 4 calories per gram.
  • Fats (30%): Crucial for hormonal health and vitamin absorption. Contains 9 calories per gram.

Calculation Example

Example: A 200lb male, 6'0″ tall, 25 years old, who works out 4 days a week (Moderately Active) and wants to lose weight.

Step-by-step solution:

  1. BMR Calculation: (10 × 90.7kg) + (6.25 × 182.8cm) – (5 × 25) + 5 = 1,930 Calories.
  2. TDEE Calculation: 1,930 × 1.55 = 2,992 Calories.
  3. Goal Adjustment: 2,992 – 500 (Deficit) = 2,492 Calories/day.
  4. Macro Split (30/40/30):
    • Protein: (2,492 × 0.30) / 4 = 187g
    • Carbs: (2,492 × 0.40) / 4 = 249g
    • Fats: (2,492 × 0.30) / 9 = 83g

Common Questions

Should I adjust my macros on rest days?

While some people prefer "calorie cycling" (higher carbs on training days, lower carbs on rest days), the most important factor for success is your weekly average. The free macro calculator provides a consistent daily target that simplifies the process and ensures sustainability.

What is the most important macro for fat loss?

Protein is generally considered the most critical macro during a fat-loss phase. It has the highest thermic effect of food (TEF), meaning your body burns more calories digesting it, and it helps preserve lean muscle tissue while you are in a caloric deficit.

How often should I recalculate my macros?

You should recalculate your macros every 10–15 pounds of weight change. As your body mass changes, your BMR and TDEE will also shift, requiring a new caloric baseline to maintain progress.

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