What is the difference between BMR and TDEE?

BMR is calories burned at rest. TDEE is BMR plus everything else — walking, working, working out, digesting food.

Why do men and women have different formulas?

Men typically have more muscle mass, which burns more calories at rest. The constants in each formula reflect that average difference.

Can I lose weight by eating below my BMR?

Not safely for long. Eating below BMR triggers metabolic adaptation, muscle loss, and hormonal disruption. Aim for 300–700 kcal below TDEE instead.

BMR Calculator

Enter your age, sex, weight, and height. Your BMR is the baseline calories your body needs just to stay alive — before any activity.

By Numerly · Updated June 14, 2026

Units

Sex

Age

yrs

Weight

Height

BMR (per day)

1717.5 kcal

Per hour at rest

71.5625 kcal

How it works

Mifflin-St Jeor formula. Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5. Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161. To get total daily calories, multiply BMR by your activity factor (use the TDEE calculator for that).

Frequently asked

What is the difference between BMR and TDEE?: BMR is calories burned at rest. TDEE is BMR plus everything else — walking, working, working out, digesting food.
Why do men and women have different formulas?: Men typically have more muscle mass, which burns more calories at rest. The constants in each formula reflect that average difference.
Can I lose weight by eating below my BMR?: Not safely for long. Eating below BMR triggers metabolic adaptation, muscle loss, and hormonal disruption. Aim for 300–700 kcal below TDEE instead.

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