Free Tool
Calorie Calculator
Find exactly how many calories you need per day to lose fat, build muscle, or maintain your weight — using the clinically validated Mifflin-St Jeor equation.
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How Many Calories Do You Actually Need?
The idea that everyone needs exactly 2,000 calories per day is a myth. Your actual calorie needs depend on a complex interaction of age, sex, height, weight, activity level, and body composition. A 25-year-old male athlete and a 50-year-old sedentary woman can have calorie needs that differ by more than 1,000 calories per day.
Calories in vs. calories out is still the fundamental law of weight change. But "calories out" is far more nuanced than most people realize — it includes your BMR (brain, heart, kidneys at rest), the thermic effect of food (digesting and absorbing nutrients), non-exercise activity thermogenesis (fidgeting, posture, walking), and planned exercise.
Frequently Asked Questions
What is TDEE?
TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a day, including your Basal Metabolic Rate (BMR) plus calories burned through physical activity, digestion, and non-exercise movement. Your TDEE is your maintenance calorie level: eating at TDEE keeps your weight stable, below it loses fat, above it gains mass.
How many calories should I eat to lose weight?
A 300–500 calorie daily deficit below your TDEE is the evidence-based recommendation for sustainable fat loss. This creates a pace of approximately 0.3–0.5 kg (0.6–1 lb) of fat loss per week — fast enough to see results but slow enough to preserve muscle.
How accurate is the calorie calculator?
The calculator uses the Mifflin-St Jeor equation, which has been validated in multiple clinical studies as the most accurate BMR formula for most people. It is within ±200 calories for most adults. Individual variation exists due to genetics, gut microbiome, and hormonal factors.
Should I eat back calories burned from exercise?
Partially. The activity multiplier already accounts for planned exercise. If you track your calories using 'sedentary' setting and then exercise, eating back 50% of exercise calories is a common approach to avoid over-restricting while keeping a meaningful deficit.
Why am I not losing weight at my calculated calorie target?
Common reasons: inaccurate food logging (portion sizes are typically underestimated by 20–30%), eating more on weekends, metabolic adaptation after prolonged dieting, high stress/cortisol increasing water retention, or medications affecting metabolism. Recalculate every 4–6 weeks as your weight changes.
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Turn Your Calorie Target Into Real Meals
Browse free recipes with full nutrition facts to find meals that fit your daily calorie target.
Browse Free RecipesMethod: Mifflin-St Jeor basal metabolic rate (Mifflin et al., Am J Clin Nutr 1990) multiplied by a standard activity factor. See full methodology and limitations. Estimates for general education, not medical advice.