BMR / TDEE Calculator

What is BMR and TDEE?

BMR (Basal Metabolic Rate) is roughly how many calories your body burns at complete rest just to keep essential functions running — breathing, circulation, cell repair. TDEE (Total Daily Energy Expenditure) takes that baseline and scales it up by an activity multiplier to estimate your actual total calories burned in a day, including exercise and daily movement.

The formula used

This calculator uses the Mifflin-St Jeor equation, published in 1990 and widely regarded by dietitians as more accurate for most people than the older Harris-Benedict equation:

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

TDEE is then BMR multiplied by an activity factor ranging from 1.2 (sedentary) to 1.9 (extra active) — the standard multiplier set commonly paired with this equation.

An honest accuracy note

Both BMR and TDEE are population-average estimates, not a direct measurement of your individual metabolism, which is genuinely influenced by muscle mass, genetics, hormones and other factors this formula can't see. Use the result as a reasonable starting point for setting a calorie target, and adjust based on your own real-world weight trend over a few weeks rather than treating the number as exact.