Calories (BMR)

BMR, or Basal Metabolic Rate, is the energy your body burns at complete rest just to keep organs working. This tool uses the Mifflin-St Jeor formula, which takes weight, height, age and sex. For a 30-year-old man at 70 kg and 175 cm, BMR is roughly 1650 kcal per day, the bare minimum you need.

Enter your weight, height, age and sex to get BMR, then multiply it by an activity factor: 1.2 for sedentary desk work, 1.55 for moderate exercise three to five days a week, and 1.725 for hard daily training. The calculator shows the multiplied total daily energy expenditure, which is what you should eat to maintain weight.

BMR depends on body size, age and sex, not on what cuisine you eat. So a vegetarian Indian thali eater and a non-vegetarian have the same BMR at the same body stats. What changes is how easily you hit that calorie target; rice, ghee and sweets pack calories fast, while sabzi and salads are lighter.

Apps often use the older Harris-Benedict equation or the Katch-McArdle formula, which need body-fat percentage. Mifflin-St Jeor is now considered more accurate for the general population and is what most dietitians use. A 50 to 100 kcal gap between tools is normal, so do not stress over small differences.

BMR is just the resting baseline; TDEE, or Total Daily Energy Expenditure, includes movement and exercise. For weight loss, eat 300 to 500 kcal below your TDEE, not below your BMR. Eating under BMR for long stretches can slow metabolism and cause fatigue, hair fall and other issues, especially in women.

Yes. Find your TDEE and then add 250 to 500 kcal for a steady, mostly-lean gain of around half a kilo per week. For Indian eaters, that often means an extra paratha, a glass of milk, and a handful of nuts on top of regular meals. Pair it with strength training so the gain is muscle, not just fat.