Free Macro Calculator

How This Calculator Works

Our macro calculator uses the Mifflin-St Jeor equation — the most accurate formula for estimating your basal metabolic rate (BMR). We then multiply by your activity level to get your Total Daily Energy Expenditure (TDEE).

Based on your goal, we adjust calories up or down and split them into optimal protein, carb, and fat ratios. Here's what happens behind the scenes:

1. Calculate BMR using your age, gender, height, and weight
2. Multiply by activity factor to get your TDEE
3. Apply goal adjustment (deficit for fat loss, surplus for muscle gain)
4. Split into macros based on evidence-based ratios

Understanding Your Results

Your Protein Target

Protein is set higher than traditional recommendations because research consistently shows that higher protein intake preserves muscle during fat loss and supports muscle growth. We target 0.8-1g per pound of bodyweight depending on your goal.

Your Carbohydrate Target

Carbs are your body's preferred energy source, especially for intense exercise. We don't go ultra-low carb because sustainable diets include carbs. Adjust up if you're very active, down if you prefer a lower-carb approach.

Your Fat Target

Fats are essential for hormone production, brain function, and nutrient absorption. We keep fats at a minimum of 0.3g per pound of bodyweight to ensure hormonal health.

Frequently Asked Questions

How accurate is this calculator?

Very accurate as a starting point. The Mifflin-St Jeor equation has been validated in numerous studies. However, individual metabolism varies — use these numbers for 2-3 weeks, track your results, and adjust if needed.

Should I eat back exercise calories?

Generally, no. Activity multipliers already account for your exercise. Eating back calories often leads to overestimating burn and slowing progress. If you're doing extreme amounts of exercise (2+ hours daily), you may need to add some back.

What if I'm not losing/gaining weight?

Give it at least 2-3 weeks first — weight fluctuates daily. If no change after 3 weeks, adjust calories by 200-300 in the direction of your goal. Also ensure you're tracking accurately (weighing food, logging everything).

How often should I recalculate?

Every 10-15 pounds of weight change, or every 4-6 weeks if progress stalls. As your body changes, your calorie needs change too.

What's the best macro split?

There's no universally "best" split — it depends on your preferences and goals. Our defaults are evidence-based, but you can adjust carbs and fats to fit your lifestyle. Just keep protein consistent.