Calorie / TDEE Calculator

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in 24 hours, including basal metabolism, daily movement, exercise, and digestion. It's the single most useful number for nutrition planning. Eat at your TDEE to maintain weight, below it to lose, above it to gain. Your TDEE shifts with weight changes, activity level, and age, so it's worth recalculating every few months.

BMR (Basal Metabolic Rate) is the calories your body burns at complete rest — just keeping organs running, maintaining body temperature, and basic cellular function. It's typically 60–75% of your TDEE. TDEE adds the energy you burn through movement, exercise, and digesting food. BMR is a baseline; TDEE is the practical number for diet planning.

Mifflin-St Jeor (1990) is the most accurate predictive equation in common use, validated across thousands of subjects. Typical error is ±10% — meaning your true TDEE is usually within 200–400 calories of the estimate. It's more accurate than the older Harris-Benedict equation (1919), which tends to overestimate. The most accurate method is indirect calorimetry in a lab, but Mifflin-St Jeor is the practical standard used by dietitians and the Academy of Nutrition and Dietetics.

Be honest. Sedentary (×1.2): desk job, almost no exercise. Light (×1.375): light exercise 1–3 days/week (walking, casual cycling). Moderate (×1.55): structured exercise 3–5 days/week (running, lifting, sports). Active (×1.725): hard exercise 6–7 days/week (training for a competition). Very active (×1.9): physical labor job plus daily training. Most US adults overestimate — a 30-minute walk 3x/week is closer to 'light' than 'moderate'.

A pound of body fat stores roughly 3,500 calories, so a 500-calorie daily deficit produces about 1 pound per week of weight loss. For 2 lb/week, you'd need a 1,000-calorie deficit, which most experts consider too aggressive for sustained dieting because it accelerates muscle loss and metabolic slowdown. A 0.5–1% of body weight per week loss rate is the standard recommendation for preserving lean mass.

No — your activity multiplier already includes exercise. Adding 'exercise calories' on top of TDEE double-counts and is the most common mistake people make. The exception: if you used the sedentary multiplier (×1.2) for your baseline and then exercise occasionally, you can add back exercise calories on training days. Fitness trackers tend to overestimate exercise burn by 30–50%, so trust them with skepticism.

A common starting point is 30% protein, 40% carbohydrates, 30% fat — solid for most adults aiming for body composition change. For active people and those losing weight, prioritize protein at 0.7–1 gram per pound of body weight (about 150–200g/day for most adults), with carbs and fat filling the rest. Protein has 4 cal/g, carbs 4 cal/g, fat 9 cal/g. Fat shouldn't drop below 20% of calories because of hormonal function; carbs and fat can be flexed based on preference.

For some people, briefly — but as a sustained intake it's lower than most adults should go without medical supervision. 1,200 calories is the floor often quoted for women and 1,500 for men, below which it becomes hard to get adequate protein, vitamins, and minerals from food. Very low calorie diets also accelerate muscle loss and metabolic adaptation. If your calculated cut puts you below these floors, eat less aggressively over a longer timeline, or consult a dietitian.

Two reasons. First, a smaller body simply requires fewer calories to maintain — less mass to move and to keep warm. Second, your body adapts to a deficit by becoming more metabolically efficient, lowering NEAT (non-exercise activity thermogenesis) — you fidget less, move less unconsciously, feel more tired. This metabolic adaptation can suppress TDEE by 5–15% beyond what mass loss alone predicts. It's why hitting a plateau is normal and why long maintenance breaks ('diet breaks') help.

If you have a medical condition (diabetes, thyroid issues, eating disorder history, kidney disease, pregnancy), yes — a registered dietitian (RD or RDN in the US) is worth the investment. They can run actual metabolic testing if needed and account for your full health picture. For an otherwise healthy adult looking to manage weight, this calculator plus consistent tracking for 4–8 weeks usually gives enough information to make informed choices. Many US health plans now cover dietitian visits — worth checking.