How the calorie calculator works
This calculator uses the Mifflin-St Jeor equation, widely regarded as one of the more accurate BMR formulas for the general population:
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
Your Total Daily Energy Expenditure (TDEE) then multiplies BMR by an activity factor to estimate the calories you burn in a full day, including movement and exercise.
Step-by-step guide
- Select your biological sex (used because it affects the BMR formula).
- Enter your age, height and current weight.
- Choose the activity level that best matches your typical week.
- Read your BMR, maintenance calories (TDEE), and adjusted targets for mild weight loss or gain.
Using your result
Track your weight over 2–3 weeks at your calculated maintenance calories. If your weight is trending up or down when you expected it to hold steady, adjust intake by roughly 100–200 kcal and reassess — individual metabolism varies enough that fine-tuning against real results beats relying on the formula alone.
Frequently asked questions
BMR is the energy your body needs at complete rest just to function. TDEE adds in the calories burned through daily movement, exercise, and digestion — it's the number most people should use to plan calorie intake.
A common approach is a moderate deficit of roughly 300–500 kcal/day below TDEE for gradual, sustainable weight loss — the 'mild weight loss' figure above reflects this. Very aggressive deficits can be harder to sustain and risk nutrient shortfalls.
It's a population-average estimate. Individual metabolism varies with muscle mass, genetics, hormonal factors and medical conditions, so treat the result as a starting point to adjust based on real-world results over a few weeks.