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Basal Metabolic Rate

Calories your body burns at complete rest — keeping organs running, blood pumping, brain active. Uses the Mifflin-St Jeor equation, the most accurate for healthy adults.

Your BMR

1700 kcal/day

If you stayed in bed all day, this is what you'd burn.

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How it's calculated

The Mifflin-St Jeor equation, published in 1990, is the most accurate formula for predicting BMR in healthy adults:

  • Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
  • Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161

BMR vs TDEE

BMR is what you burn at rest. TDEE includes activity. Your real maintenance calories are TDEE, not BMR — never eat below your BMR for sustained periods.

What affects BMR

  • Muscle mass — more muscle = higher BMR
  • Age — BMR drops ~1-2% per decade after 20
  • Sex — men have 5-10% higher BMR than women at same height/weight
  • Genetics — natural variation of ±200 kcal between similar individuals

Next: calculate your TDEE

BMR alone isn't your maintenance number. TDEE Calculator multiplies BMR by your activity level to give the actual calories you burn per day.