Find your Total Daily Energy Expenditure — exactly how many calories you need to maintain, lose, or gain weight. Based on the Mifflin-St Jeor equation.
yrs
kg
cm
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Lose weight −500 cal/day
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Maintain current weight
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Gain weight +500 cal/day
BMR (basal metabolic rate)—
Activity multiplier—
TDEE (maintenance calories)—
To lose 0.5 kg/week—
To gain 0.5 kg/week—
Note: Mifflin-St Jeor is the most validated BMR formula for most people. Actual needs vary by muscle mass, genetics, and health. Adjust based on real-world results over 2–4 weeks of consistent tracking.
How to Calculate Your Daily Calorie Needs (TDEE)
Your Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day — including everything from keeping your heart beating to running a 5K. It's the single most important number for anyone trying to manage their weight, and the calculator above estimates it using the most accurate formula available for non-clinical settings.
TDEE is calculated in two steps: first, estimating your Basal Metabolic Rate (BMR) — the calories burned at complete rest — then multiplying by an activity factor that accounts for how physically active you are. The result is your maintenance calorie level: eating exactly this amount keeps your weight stable.
The Mifflin-St Jeor Formula Explained
This calculator uses the Mifflin-St Jeor equation, the formula recommended by the Academy of Nutrition and Dietetics as the most accurate for estimating BMR in most adults. Published in 1990 and validated in dozens of subsequent studies, it outperforms the older Harris-Benedict equation (1919) by approximately 5% in accuracy:
A deficit of 500 calories per day below your TDEE leads to roughly 0.5 kg (1 lb) of fat loss per week — a rate consistently supported by research as safe and sustainable. Larger deficits (1,000+ cal/day) can accelerate weight loss but risk muscle loss, metabolic adaptation, nutrient deficiencies, and rebound weight gain. The goal is to eat as much as possible while still losing fat — not to eat as little as possible.
Minimum recommended intake: 1,200 cal/day for women, 1,500 cal/day for men (without medical supervision)
Sustainable loss rate: 0.5–1% of body weight per week
Track for 2–4 weeks: Adjust by 100–200 cal based on actual results, since TDEE estimates have ±15% margin
Sleep's Impact on Calories and Weight
Poor sleep directly increases calorie intake. Sleep deprivation elevates ghrelin (hunger hormone) by up to 28% and reduces leptin (fullness hormone) by 18%, driving increased appetite — especially for high-calorie, carbohydrate-rich foods. Studies show sleep-deprived adults eat 200–550 extra calories per day on average. Consistently getting 7–9 hours of quality sleep is one of the most effective (and most overlooked) tools for calorie management and healthy weight.
TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a full day, including exercise, daily movement, and basic metabolic functions. It's your BMR (calories burned at complete rest) multiplied by an activity factor. Eating at your TDEE maintains your weight; eating below it causes weight loss; eating above it causes weight gain. It's the foundation of evidence-based nutrition planning.
How many calories should I eat to lose weight?
A deficit of 500 calories per day below your TDEE leads to approximately 0.5 kg (1 lb) of fat loss per week. This is the most sustainable and research-supported rate. Deficits larger than 1,000 cal/day are generally not recommended without medical supervision as they increase risk of muscle loss, metabolic slowdown, and micronutrient deficiencies. Aim for slow, steady loss — it produces better long-term results than aggressive restriction.
Why isn't my calorie calculation working for me?
TDEE formulas have a margin of error of approximately ±15% due to individual variation in metabolism, gut microbiome, muscle mass, NEAT (non-exercise activity thermogenesis), and hormonal factors. If you're eating at your calculated TDEE for 3–4 weeks without expected results, adjust by 100–200 calories in the appropriate direction and track for another 2–4 weeks. Real-world tracking outperforms any formula.
Does sleep affect calorie burning and weight?
Yes, significantly. Poor sleep increases hunger hormones (ghrelin up 28%) and decreases satiety hormones (leptin down 18%), leading to 200–550 extra calories consumed per day on average. Sleep deprivation also reduces willpower and impulse control, making high-calorie food choices more likely. Additionally, less sleep = less energy for activity, further reducing calorie burn. Getting 7–9 hours of quality sleep is one of the most underrated factors in weight management.
What is BMR and how is it different from TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — just to maintain vital organ functions (breathing, circulation, cell repair). TDEE adds the calories burned through all physical activity. BMR typically accounts for 60–75% of total daily energy expenditure. The remaining 25–40% comes from exercise, daily movement (NEAT), and digesting food (thermic effect of food, ~10% of intake).