Calorie (TDEE) Calculator

The tool works in two steps. First it estimates your resting energy use with the Mifflin-St Jeor equation (1990), which the original paper calls resting energy expenditure:

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

Then it multiplies that by a fixed factor for the activity level you choose: 1.2, 1.375, 1.55, 1.725 or 1.9. With the defaults (male, 30 years, 175 cm, 70 kg, moderate activity) the resting figure is 1,648.75 kcal and maintenance is 1,648.75 × 1.55 = 2,556 kcal/day.

Treat the result as an estimate of what you burn, not a measurement and not a diagnosis.

The activity choice moves the answer more than any other input. Here is the default profile run through every option:

Sedentary and very active are 1,154 kcal apart for the same body. By comparison, adding 10 kg raises maintenance by only 155 kcal at the moderate level. If you can't decide between two levels, run both and treat the gap as the uncertainty in your estimate.

Below the maintenance figure, the tool subtracts or adds a fixed 275 or 550 kcal. The offset is the same for everyone, whatever their size, so it is a much bigger cut for a small, inactive person than for a large, active one:

• A 30-year-old woman, 165 cm, 62 kg, sedentary: maintenance 1,608, and the 550 box shows 1,058, about 34% less.
• The default man at very active: 3,133 down to 2,583, about 18% less.

The weekly rates printed on the box labels are the tool's own rough guide. How your weight responds in practice varies from person to person, so use the boxes as reference points rather than promises.

Age costs 5 kcal of resting energy per year in the equation, so ten years lowers moderate-activity maintenance by about 78 kcal. Height adds 6.25 kcal per centimetre before the multiplier. The equation uses total weight, not body composition, and there is no box for body fat, so two people of the same sex, age, height and weight always get the same answer.

If you only want the resting figure without any activity factor, the BMR Calculator shows that step on its own.