🔥 Calorie Calculator (BMR & TDEE)
Find out how many calories you burn per day, what to eat to lose or gain weight, and how many grams of carbs, protein and fat that means. Works in pounds and feet or kilograms and centimeters.
How to use the calorie calculator
- Pick US units (pounds, feet and inches) or Metric (kilograms, centimeters), then enter your sex, age, height and weight.
- Choose your typical activity level. Think about your job as well as your workouts — a nurse on their feet all day burns more than an office worker who runs twice a week. If you are unsure, pick the lower option; most people overestimate their activity.
- The big number is your maintenance calories (TDEE) — what you can eat per day to stay at the same weight. Below it you get a weight-loss and weight-gain target and an example macro split in grams.
BMR vs. TDEE
Basal metabolic rate (BMR) is the energy your body uses just to stay alive at rest — breathing, circulation, keeping warm. You also burn calories walking, working, exercising and digesting food, so your total daily energy expenditure (TDEE) is BMR multiplied by an activity factor.
Over time your weight follows calories eaten − TDEE. Eat at TDEE and you maintain; eat less and you lose; eat more and you gain.
Formulas used
- Mifflin-St Jeor (default) — men
10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5, women10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. It is the equation most dietitians use today because it tends to be closest to measured values. - Revised Harris-Benedict (for reference) — men
88.362 + 13.397 × kg + 4.799 × cm − 5.677 × age, women447.593 + 9.247 × kg + 3.098 × cm − 4.330 × age. The 1919 equation refit in 1984; it usually comes out a little higher. - TDEE =
BMR × activity factor - Macros in grams =
calories × share ÷ (4 kcal/g for carbs and protein, 9 kcal/g for fat) - US inputs are converted first:
1 lb = 0.45359237 kg,1 in = 2.54 cm.
| Activity level | Factor | Example |
|---|---|---|
| Sedentary | 1.2 | Desk job, no exercise |
| Lightly active | 1.375 | Light workouts 1–3 days a week |
| Moderately active | 1.55 | Workouts 3–5 days a week |
| Very active | 1.725 | Hard training 6–7 days a week |
| Extra active | 1.9 | Physical job plus training, athletes |
Example: 32-year-old man, 5'8", 165 lb
5'8" is 172.7 cm and 165 lb is 74.8 kg, so BMR = 10 × 74.8 + 6.25 × 172.7 − 5 × 32 + 5 ≈ 1,673 kcal. Lightly active (× 1.375) gives a TDEE of about 2,300 kcal. A −500 kcal deficit puts the weight-loss target near 1,800 kcal a day.
Why −500 and +300 calories?
A pound of body fat is often estimated at about 3,500 kcal (roughly 7,700 kcal per kg), so a 500 kcal daily deficit works out to about 1 lb per week on paper. It is a common, sustainable starting point — bigger deficits make muscle loss, fatigue and rebound weight gain more likely. For gaining, a modest +300 kcal surplus limits fat gain. Real bodies adapt, so watch your 2–3 week weight trend and adjust by 100–200 kcal.
Calorie calculator vs. BMI
BMI classifies your current size from height and weight; a calorie calculator estimates how much to eat. Two people with the same BMI can need very different calories depending on muscle mass and activity.
These numbers are statistical estimates, not medical advice. If you are pregnant or breastfeeding, a teenager, have a health condition (diabetes, kidney disease, etc.) or take medication, talk to a doctor or registered dietitian before changing your diet. Diets below about 1,200 kcal for women or 1,500 kcal for men are generally not recommended without supervision.