Calorie Calculator
Estimate your daily calorie needs for weight loss, maintenance, or gain.
How the Calorie Calculator Works
The Mifflin-St Jeor equation, published in 1990 and recommended by the American Dietetic Association, is considered the most accurate formula for estimating resting metabolic rate (RMR). This calculator uses it to determine your Basal Metabolic Rate (BMR) — the number of calories your body burns at rest to maintain basic life functions such as breathing, circulation, and cell production. The formula differs by sex: for men, BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) + 5; for women, the same calculation applies but with -161 instead of +5.
For example, a 30-year-old male who is 175 cm tall and weighs 70 kg would have a BMR of (10 x 70) + (6.25 x 175) - (5 x 30) + 5 = 700 + 1093.75 - 150 + 5 = 1,648.75 kcal/day. This means his body requires roughly 1,649 calories per day just to sustain vital functions at complete rest, before any physical activity is factored in.
Your Total Daily Energy Expenditure (TDEE) is then calculated by multiplying your BMR by an activity multiplier. The five activity levels correspond to specific multipliers: Sedentary (x1.2) for desk jobs with little exercise, Lightly Active (x1.375) for light exercise 1-3 days per week, Moderately Active (x1.55) for moderate exercise 3-5 days per week, Active (x1.725) for hard exercise 6-7 days per week, and Very Active (x1.9) for athletes or those with physically demanding jobs who also train.
Using our example, the 30-year-old male with a BMR of 1,649 kcal who exercises 3-5 days per week (Moderately Active) would have a TDEE of 1,649 x 1.55 = approximately 2,556 kcal/day. This is the number of calories he needs to maintain his current weight. To lose weight at a safe rate of about 0.5 kg (1 lb) per week, he would reduce intake by 500 kcal to roughly 2,056 kcal/day. For a detailed weight loss plan with timeline, try our calorie deficit calculator.
The calorie goals displayed adjust your TDEE in increments to support various weight management objectives. Mild weight loss (-250 kcal/day) and mild weight gain (+250 kcal/day) offer gradual, sustainable changes, while more aggressive targets (-500 or -1,000 kcal/day) accelerate results but should be approached with caution. It is generally not recommended to consume fewer than 1,200 kcal/day for women or 1,500 kcal/day for men without medical supervision.