Macros Calculator
Calculate your TDEE and get personalized macronutrient targets. Uses the Mifflin-St Jeor equation — the most accurate predictive formula for BMR.
The Macros Approach
If you want to go deeper than simple calorie counting, tracking macronutrients (macros) gives you more control over your body composition. Three macronutrients provide all of your dietary calories:
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Protein
4 cal/g
Builds and repairs muscle. Most important macro for body composition. Highest satiety.
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Fat
9 cal/g
Hormone production, vitamin absorption, cell membranes. Essential — never cut below 20%.
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Carbs
4 cal/g
Primary energy source. Performance fuel. Fills in remaining calories after protein and fat.
Our Allocation Strategy
This calculator uses an evidence-based allocation:
- Protein: 1 g per lb of body weight (deficit: 0.8 g/lb, surplus: 1 g/lb). Higher protein during a deficit preserves muscle mass.
- Fat: 25% of total calories. Ensures hormonal health without over-allocating.
- Carbs: The remainder. Carbs are the flexible macro — adjust based on preference and performance.
The Fat Loss Math
One pound of body fat ≈ 3,500 stored calories. To lose 1 lb/week, you need a daily deficit of 500 calories. To lose 2 lbs/week, 1,000/day. Most people should aim for 1-1.5 lbs/week — aggressive deficits lead to muscle loss and metabolic adaptation.
Example Macro Split — 2,000 cal/day
About the Mifflin-St Jeor Equation
Published in 1990, the Mifflin-St Jeor equation is the most accurate predictive formula for Basal Metabolic Rate (BMR) in most adults:
- Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
- Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Your TDEE (Total Daily Energy Expenditure) = BMR × Activity Multiplier. This calculator supports 5 activity levels and 6 different goals.
Calculate Your Macros
Macro Tracking Tools
Digital Food Scale
Accurate macro tracking starts with accurate portions. A kitchen scale is the single most impactful tool you can buy.
Shop on Amazon →High-Protein Cookbook
Cookbook focused on high-protein meals with macro breakdowns. Takes the guesswork out of hitting your targets.
Shop on Amazon →Meal Prep Containers
Portion-controlled containers make it easy to prep a week of meals that hit your macro targets consistently.
Shop on Amazon →Protein Powder
When whole foods aren't enough, protein powder is the most efficient way to hit your protein target. Look for isolate with minimal added sugar.
Shop on Amazon →As an Amazon Associate, I earn from qualifying purchases. Product links on this page are affiliate links — they cost you nothing extra.
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