What is the difference between BMR and maintenance calories?

BMR is the energy your body needs at complete rest to keep basic functions such as breathing and circulation going. Maintenance calories, or TDEE, add the energy you use for daily movement and exercise, so they are always higher than your BMR.

Why does the calculator use the Mifflin-St Jeor equation?

Mifflin-St Jeor was published in 1990 and, in comparison studies, has tended to predict resting energy use more accurately than older equations such as the original Harris-Benedict formula for most healthy adults.

How many calories should I cut to lose weight?

A deficit of about 250 to 500 kcal per day is a moderate approach that is often linked with losing around 0.25 to 0.5 kg (0.5 to 1 lb) per week. Larger deficits are harder to keep up and may lead to muscle loss.

Which activity level should I choose?

Pick the level that matches an ordinary week rather than your best week. Most people with desk jobs who exercise a few times a week fit the light or moderate level. If you are unsure, choose the lower option and adjust later based on your results.

Calorie Calculator – Daily Calories to Maintain, Lose or Gain

How to use the calorie calculator

Select US or Metric units, then enter your age (15 to 80), sex, weight and height and pick the activity level that best describes a typical week. Press Calculate to see your basal metabolic rate (BMR), your maintenance calories and daily targets for gaining or losing weight at two different speeds.

The formulas

Basal metabolic rate

Your BMR is the energy your body uses at complete rest. The calculator uses the Mifflin-St Jeor equation (1990), which studies have found to be one of the more reliable predictive equations for healthy adults:

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

Maintenance calories

Total daily energy expenditure (TDEE) is the BMR multiplied by an activity factor:

Sedentary (little or no exercise): 1.2
Light (exercise 1–3 days a week): 1.375
Moderate (exercise 3–5 days a week): 1.55
Very active (hard exercise 6–7 days a week): 1.725
Extra active (very hard exercise or a physical job): 1.9

Worked example

A 30-year-old man who weighs 80 kg (176 lb), is 180 cm (5 ft 11 in) tall and exercises moderately has a BMR of 10 × 80 + 6.25 × 180 − 5 × 30 + 5 = 1,780 kcal. His maintenance level is 1,780 × 1.55 ≈ 2,759 kcal per day. Eating about 2,259 kcal a day (500 less) would be expected to lead to a loss of roughly 0.5 kg (1 lb) per week.

Weight loss and gain targets

The targets add or subtract 250 or 500 kcal per day from your maintenance level. A daily difference of about 500 kcal is a common rule of thumb for changing weight by around 1 lb a week, but real progress varies because the body adapts as weight changes.

The calculator warns you when a target drops below 1,200 kcal a day for women or 1,500 kcal a day for men. Eating less than this makes it hard to get enough nutrients and is generally only advised under medical supervision.

Good to know

All formulas give estimates. Your real needs can differ by a few hundred calories because of genetics, body composition and health conditions.
People with a lot of muscle usually burn more than the equation predicts, while people with a high body fat percentage may burn less.
Track your weight for a few weeks and adjust your intake if the results do not match the estimate.
This calculator is not suitable during pregnancy or breastfeeding. The results are not medical advice, so speak to a doctor or registered dietitian before making major changes to your diet.