Calorie Calculator

The Calorie Calculator estimates total daily energy expenditure (TDEE) — the number of calories you burn in an average day — from your sex, age, height, weight and activity level. It uses the Mifflin–St Jeor equation, which most dietitians and sports-nutrition references consider the most accurate general-purpose formula for estimating basal metabolic rate (BMR) in healthy adults, ahead of older formulas like Harris-Benedict.

BMR is calculated as 10 × weight in kilograms + 6.25 × height in centimeters − 5 × age in years, plus 5 for men or minus 161 for women — the energy your body would burn lying still for 24 hours. That BMR is then multiplied by an activity factor ranging from sedentary to extra active to produce TDEE, which reflects your actual daily calorie needs including exercise and general movement, not just resting metabolism.

Alongside maintenance calories, the calculator shows daily targets for mild and standard weight loss (a 250 and 500 calorie daily deficit) and for gaining weight (a 250 and 500 calorie daily surplus), which correspond to roughly a quarter and half a kilogram of change per week. That rate of change is based on the widely used estimate that a pound of body fat stores roughly 3,500 kcal, so a consistent daily deficit or surplus translates fairly predictably into weekly weight change over time.

Both metric and imperial units are supported, and every calculation happens instantly in your browser with nothing stored or transmitted. This TDEE calculator gives an estimate of daily calorie needs for generally healthy adults — it isn't a substitute for individualized medical or nutritional advice, and anyone with a medical condition, or making a significant change to their diet, should talk to a doctor or registered dietitian first. Pairing the result with a BMI check gives a fuller picture of where you're starting from before setting a calorie target.