BMR Calculator
Calculate your basal metabolic rate — calories burned at rest.
Basal metabolic rate
1,649 kcal
calories burned at complete rest, per day
Per hour
69 kcal
Sedentary day (×1.2)
1,979 kcal
What BMR measures
Basal metabolic rate is the energy your body spends just staying alive — heartbeat, breathing, brain, cell repair — measured at rest. It typically accounts for 60–70% of total daily burn. This calculator uses the Mifflin-St Jeor equation, the formula clinical research has found most accurate for modern populations.
What moves it
Lean mass is the biggest controllable driver — muscle burns more at rest than fat, which is why strength training nudges BMR upward. Aggressive dieting works the other way: prolonged large deficits can suppress metabolic rate as the body adapts.
Frequently asked questions
What's the difference between BMR and TDEE?
BMR is the energy you burn at complete rest — just keeping the body running. TDEE (total daily energy expenditure) is BMR multiplied by an activity factor to include movement and exercise. TDEE is the number to eat around for weight goals; BMR is its foundation.
How accurate is the Mifflin-St Jeor equation?
It's the formula clinical research finds most accurate for the general population, typically within about 10% of a lab measurement. Individuals vary around it, so treat the result as a starting point — track your weight for a few weeks and adjust if the scale disagrees.
Can I lose weight by eating below my BMR?
You can, but it's rarely advisable — eating below BMR for long periods is hard to sustain, risks nutrient gaps, and can accelerate muscle loss. A moderate deficit below your TDEE (not your BMR) delivers steady fat loss while preserving lean mass.
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