TDEE and Calories: How Many You Need

How to estimate your BMR with the Mifflin-St Jeor equation and your total daily calories (TDEE), and how to adjust for weight loss or gain.

BMR (Mifflin-St Jeor)

Basal metabolic rate is what you burn at rest: 10×kg + 6.25×cm − 5×age + (5 for men, −161 for women).

TDEE = BMR × activity

Multiply BMR by an activity factor (sedentary 1.2 up to very active 1.9). The result is roughly the calories to maintain your weight.

Losing or gaining

Eating about 500 kcal below TDEE targets roughly 1 lb of loss per week; a surplus supports gaining. Individual results vary.

FAQ

Which activity level do I pick?

Base it on weekly exercise: little (1.2), moderate 3–5 days (1.55), daily or intense (1.725+).

Are these numbers exact?

They are estimates. Metabolism varies by person, so adjust based on real results over a few weeks.

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Last updated: 2026-07-25 · This content is a 2026 reference and may differ from actual rules and rates.