Looking for a bmr calculator calories your body burns at rest? This free tool gives you resting calories plus TDEE for five activity levels. Just enter your numbers and press Calculate — results are instant.
BMR (Basal Metabolic Rate) is the energy your body burns just to stay alive — breathing, keeping warm, running your organs — before any movement at all. This calculator uses the Mifflin-St Jeor equation, which takes your sex, age, height and weight. Multiply the BMR by an activity factor (1.2 for a desk job up to 1.725 for very active) to estimate the calories you burn in a whole day.
Example: Male · Age 30 · Height 175 cm · Weight 75 kg
BMR (calories / day at rest): 1,699
BMR is what you burn at rest. TDEE (total daily energy expenditure) is BMR times your activity factor — what you burn in a whole day including movement. This calculator shows both.
Yes. Muscle burns more energy at rest than fat does, so two people of the same weight can have different BMRs. The Mifflin-St Jeor equation uses weight, height, age and sex, and cannot see body composition, so it is an estimate.
Yes, slowly — roughly a few percent per decade, mostly because muscle is lost with age. Staying active and keeping muscle helps hold it up.