About the BMR & Calorie Calculator
The BMR and calorie calculator estimates how many calories your body uses: at complete rest (your basal metabolic rate, BMR), and in a whole day with your usual activity (your total daily energy expenditure, TDEE). That second number is roughly what you can eat to keep your weight.
It uses the Mifflin-St Jeor equation, which studies have found to be the most accurate of the common equations for most adults. From your daily calories it shows targets for losing or gaining weight slowly or faster, and about how much that changes your weight in a week.
Enter your height and weight in centimetres and kilograms or in feet, inches and pounds. Everything is calculated in your browser; nothing you type is stored or sent.
How to use it
- Choose your sex: the equation differs for men and women.
- Enter your age, from 18 to 100.
- Choose metric or US units and enter your height and weight.
- Choose the activity level that matches a usual week.
- Read your BMR, the calories to keep your weight, and the targets for your goal.
Features
- Mifflin-St Jeor: 10 × weight in kg + 6.25 × height in cm − 5 × age, plus 5 for men or minus 161 for women.
- Five activity levels: From a desk job with no exercise (× 1.2) to hard training or a physical job (× 1.9).
- Goals with a week’s change: Targets from 250 to 1,000 kcal a day below or above your needs, with about how much weight that is in a week.
- Metric or US units: Centimetres and kilograms, or feet, inches and pounds, with a decimal comma where your language uses one.
- Private: Nothing you type leaves your browser.
Examples
A 30-year-old man
180 cm and 80 kg: a BMR of 1,780 kcal, and about 2,450 kcal a day with light exercise.
A 25-year-old woman
165 cm and 60 kg: a BMR of about 1,345 kcal, and about 1,850 kcal a day with light exercise.
Losing weight slowly
Eating 500 kcal a day less than your needs loses about 0.45 kg (1 lb) a week.
Limitations and notes
- It is an estimate for healthy adults. Your real needs can differ by a few hundred kilocalories a day.
- It does not fit during pregnancy or breastfeeding, under 18, for very muscular people, or with conditions that change your metabolism; talk to a doctor.
- The weekly change uses about 7,700 kcal per kilogram (3,500 per pound) of body fat; real weight changes also include water and are rarely that even.
- Targets below 1,200 kcal a day for women or 1,500 kcal for men are marked: they are not usually advised without a doctor.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is what your body burns at complete rest. TDEE adds everything you do in a day, from walking to exercise, so it is your BMR times an activity factor.
Why does it ask for my sex?
The Mifflin-St Jeor equation has one version for men and one for women, because on average their bodies use energy differently at the same size.
How many calories should I cut to lose weight?
About 500 kcal a day below your needs is a common, steady pace of about 0.5 kg (1 lb) a week. Bigger cuts are harder to keep up and are best done with advice.
Which activity level should I pick?
Pick the one that matches an ordinary week, not your best one. If you are between two, the lower one is the safer estimate.
Is what I enter saved?
No. The calculation happens in your browser, and nothing is stored or sent.