Calorie, BMI & TDEE Daily Energy Expenditure
Calculate your daily calorie needs (TDEE), BMR via Mifflin-St Jeor formula, BMI category, and target calories for fat loss or lean muscle building.
Daily Calorie Targets for Your Goal
| Fitness Objective | Daily Calorie Intake | Weekly Weight Change | Calorie Deficit / Surplus |
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🍎 The Mifflin-St Jeor Clinical Benchmark
This calculator implements the peer-reviewed Mifflin-St Jeor formula, validated by the American Dietetic Association as the most accurate clinical BMR estimation for non-obese and obese adults. When pursuing sustainable fat loss, aim for a moderate 500 kcal deficit rather than crash dieting to preserve lean muscle mass and metabolic rate.
About this tool
How to use it
- Select your unit system (Metric or Imperial) and input your biological sex, age, weight, and height.
- Choose your typical weekly physical activity multiplier (Sedentary through Extremely Active).
- Click 'Calculate Calories, BMI & TDEE' to view your daily caloric maintenance baseline.
- Review your BMR, BMI classification, healthy weight target range, and tailored caloric targets for fat loss or muscle gain.
Why it matters
Successful nutrition and body recomposition require understanding energy balance: Calories In versus Calories Out. Calculating baseline BMR and activity-adjusted TDEE provides the mathematical foundation needed to set safe, realistic calorie deficits for fat loss or surpluses for muscle hypertrophy.
When to use it
Use this calculator when planning a fitness program, beginning a calorie-tracking diet, adjusting meal portions, or benchmarking healthy weight ranges.
Good to know
Formula used: Mifflin-St Jeor Equation: BMR = 10 × weight(kg) + 6.25 × height(cm) - 5 × age(y) + s (+5 for men, -161 for women).
Common questions
What is the difference between BMR and TDEE?
Basal Metabolic Rate (BMR) is the energy your body expends just staying alive at complete rest (breathing, cellular repair, circulation). Total Daily Energy Expenditure (TDEE) accounts for all daily movement, workouts, and digestion on top of your BMR.
What is a safe calorie deficit for fat loss?
A moderate deficit of 500 calories per day produces roughly 1 pound (0.45 kg) of fat loss per week. Deficits exceeding 1,000 calories risk muscle catabolism, nutrient deficiencies, and metabolic slowdown.
Why is the Mifflin-St Jeor equation preferred over Harris-Benedict?
Clinical trials by the Academy of Nutrition and Dietetics demonstrated that Mifflin-St Jeor predicts BMR within 10% of measured indirect calorimetry in both non-obese and obese individuals, whereas Harris-Benedict tends to overestimate expenditure by 5-15%.
How does BMI relate to body fat percentage?
BMI measures weight relative to height squared. While a reliable population screening tool, it does not distinguish between lean muscle mass and adipose tissue; muscular athletes may register as 'overweight' despite low body fat.