Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Calculate your Basal Metabolic Rate using the Mifflin-St Jeor equation.
1649 kcal/day
Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to keep vital functions running -- breathing, circulation, cell production. This tool estimates it using the Mifflin-St Jeor equation (1990), which current sports-nutrition literature generally recommends over the older Harris-Benedict formula for accuracy in modern populations.
Enter your weight, height, age, and sex. Your estimated BMR appears instantly in calories per day.
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) - 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) - 5 × age - 161
BMR is the starting point for calculating your total daily calorie needs -- feed it into the TDEE Calculator to account for activity level, then use the Calorie Deficit Calculator or Calorie Surplus Calculator to set a weight-loss or weight-gain target.
Consider a hypothetical 30-year-old man who weighs 70 kg and is 175 cm tall. The calculator starts with these values. The equation gives 10 times 70, which is 700, plus 6.25 times 175, which is 1,093.75, minus 5 times 30, which is 150, and then plus 5 for men. The total is 1,648.75, displayed as about 1,649 kilocalories per day. For a hypothetical 40-year-old woman who weighs 60 kg and is 165 cm tall, the same steps give 600 plus 1,031.25 minus 200 minus 161, or about 1,270 kilocalories per day. These are estimates of energy burned at rest, not amounts anyone should eat.
Those simple slopes make it easy to sanity-check the output by hand, and to see how a change in weight over a few months will nudge the estimate.
Use kilograms for weight and centimetres for height, and enter age in whole years. All three numeric fields must be greater than zero before a result appears. Choose the sex option that matches the equation you want to apply; the formula only has these two versions, so it cannot reflect every individual. If you only know your weight in pounds, divide by 2.2046 to get kilograms, and if you only know height in feet and inches, multiply total inches by 2.54 to get centimetres.
BMR is an estimate of resting energy use, and real values differ from person to person because of muscle mass, genetics, hormones, medications, illness and other factors. The equation uses body weight rather than composition, so two people with the same height, weight and age can have different true resting rates. Do not eat at your BMR as a diet target. It excludes movement and daily activity, so eating only that amount would usually be far below what your body needs across a normal day. For planning, move on to the TDEE step, which scales BMR by an activity level.
Anyone with a medical condition, a pregnancy, or a history of disordered eating should get individual guidance from a doctor or registered dietitian before changing their intake. This tool is educational only and is not medical advice.
No -- BMR is calories burned at complete rest; TDEE adds your activity level on top. Use the TDEE Calculator for your real daily calorie needs.
The Mifflin-St Jeor equation accounts for typical differences in body composition (men generally carry more lean muscle mass, which burns more calories at rest) via a fixed offset.
Mifflin-St Jeor is considered one of the most accurate predictive equations for a general population, but individual metabolism varies -- treat it as a solid starting estimate, not an exact lab measurement.
No. BMR only covers rest. Daily movement and exercise add to it, so use a TDEE estimate for maintenance and adjust from there with professional guidance if needed.
The equation adds 5 for men and subtracts 161 for women, a difference of 166 kcal per day, which reflects average differences in body composition.
Each additional year lowers the estimated BMR by 5 kcal per day in this equation, so ten years makes a difference of 50 kcal per day, all else equal.
Not directly. The fields expect kilograms and centimetres, so convert first.
Reference: Centers for Disease Control and Prevention