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Estimate your daily calorie needs

Enter your sex, age, height, weight and activity level to estimate the calories your body uses each day and how many would maintain your weight.

Calculations run on this device. We don't see, store or log your measurements or age. This calculator gives estimates for adults and is not medical advice.

How it works

  1. Choose your sex and enter your age.
  2. Enter your height and weight in metric or imperial units.
  3. Pick the activity level that fits a typical week, then read your daily calories.

How the estimate works

BMR (calories used at rest) = 10 × weight in kg + 6.25 × height in cm − 5 × age, plus 5 for men or minus 161 for women (Mifflin–St Jeor, 1990). A 30-year-old man, 175 cm and 70 kg, has a BMR of about 1,649 kcal; mostly sitting (× 1.2) he uses about 1,979 kcal a day.

Activity levels

Sedentary × 1.2 (desk job, little exercise), light × 1.375 (exercise 1–3 days a week), moderate × 1.55 (3–5 days), active × 1.725 (6–7 days) and very active × 1.9 (physical job plus training). Most people overestimate their activity, so if unsure pick the lower level.

Losing or gaining weight

Eating about 500 kcal a day less than your total is a common starting point for losing roughly 0.5 kg a week; 500 more for gaining. Needs differ between people, and during pregnancy, illness or for athletes. This is an estimate, not medical or nutrition advice; speak to a doctor or dietitian for a plan.

Frequently asked questions

What is the difference between BMR and TDEE?

BMR is what your body uses at complete rest; TDEE adds daily activity and exercise, so it's the number that maintains your weight.

How accurate is it?

Mifflin–St Jeor is one of the most reliable equations for adults, but individual needs can still differ by about 10%. Adjust after a few weeks based on your weight.

Can teenagers use it?

No. It is designed for adults aged 18 and over.

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