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Health

BMR & TDEE Calculator

Enter sex, age, height, weight and activity level to instantly get your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Switch between Mifflin-St Jeor (recommended) and the revised Harris-Benedict formula, and see calorie targets for cutting, maintaining or bulking.

Formula
Sex

Basal Metabolic Rate (BMR)

1568

kcal/day

Daily energy need (TDEE)

2430

kcal/day

Calorie targets (reference)

  • Faster loss (−500 kcal)

    —

  • Mild loss (−250 kcal)

    —

  • Maintain weight

    —

  • Mild gain (+250 kcal)

    —

  • Faster gain (+500 kcal)

    —

For reference only. BMR is energy expenditure at complete rest; actual need varies with body fat, muscle and health status. Aim for 0.25–0.5 kg per week when losing or gaining weight.

Formula

Mifflin-St Jeor (male): BMR = 10·kg + 6.25·cm − 5·age + 5 Mifflin-St Jeor (female): BMR = 10·kg + 6.25·cm − 5·age − 161 TDEE = BMR × activity factor (1.2 / 1.375 / 1.55 / 1.725 / 1.9)

Frequently asked

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the energy your body needs at complete rest in a thermoneutral room to keep basic functions running — breathing, heartbeat, body temperature. It accounts for roughly 60–75% of total daily energy use. TDEE adds an activity multiplier on top of BMR to cover incidental movement, exercise and the thermic effect of food. TDEE — not BMR — is the actual maintenance calorie level you should anchor cutting or bulking plans to.

For Hong Kong adults, Mifflin-St Jeor or Harris-Benedict?

Generally choose Mifflin-St Jeor. The US Academy of Nutrition and Dietetics has used it as the standard since 2005, and studies show ±10% accuracy in non-obese adults. The revised Harris-Benedict tends to overestimate by 5–8% but remains popular in the fitness scene. Differences you see between trainers usually come down to formula or multiplier choice — pick one and stick with it for a few weeks before tweaking.

I want to lose weight — how many calories should I eat per day?

A healthy target is 0.25–0.5 kg per week, which requires a daily deficit of 250–500 kcal from TDEE (1 kg of body fat ≈ 7,700 kcal). The calculator shows the “mild loss” and “faster loss” numbers automatically. Do not go below ~1,200 kcal (women) / ~1,500 kcal (men), and pair the deficit with protein (1.2–2 g/kg bodyweight) and resistance training, or you will lose muscle alongside fat. If progress stalls for weeks, re-evaluate your activity multiplier or log your real intake for 2–3 weeks before adjusting.

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