What formula is used?

BMR uses the Mifflin-St Jeor equation: men = 10·kg + 6.25·cm − 5·age + 5; women = 10·kg + 6.25·cm − 5·age − 161. TDEE multiplies BMR by your activity factor.

What activity factor should I pick?

Sedentary = 1.2 (desk job, no exercise), Lightly active = 1.375 (1–3 days/week), Moderately active = 1.55 (3–5 days/week), Very active = 1.725 (6–7 days/week), Extra active = 1.9 (physical job + training).

How are loss/gain calories computed?

About 7,700 kcal ≈ 1 kg of body weight. So 500 kcal/day deficit ≈ 0.5 kg/week loss, and 1,000 kcal/day deficit ≈ 1 kg/week loss (extreme — consult a doctor).

Is BMR accurate for everyone?

Mifflin-St Jeor is more accurate than older formulas but still an estimate. It doesn't account for body composition, medical conditions or medications. Consult a registered dietitian for personalised figures.

Are my inputs stored?

No. Everything is computed locally in your browser. Nothing is sent over the network.

BMR & TDEE Calculator

Daily calorie needs for maintenance, loss and gain — Mifflin-St Jeor.

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How to use BMR & TDEE Calculator

Follow these steps — everything happens instantly in your browser.

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Step 1. Pick your biological sex and enter your age, weight and height.
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Step 2. Choose an activity level that reflects your average week.
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Step 3. Read your BMR, TDEE and six calorie targets — from extreme loss to weight gain.