Calorie Calculator
Find how many calories you should eat per day for your goal — weight loss, maintenance or muscle gain — based on your age, sex, height, weight and activity level.
How to use the Calorie Calculator
- Enter your inputs into the Calorie Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The Mifflin–St Jeor equation
BMR (men) = 10·W + 6.25·H − 5·A + 5 · · · BMR (women) = 10·W + 6.25·H − 5·A − 161 · · · TDEE = BMR × activity factor
W is weight in kg, H is height in cm, A is age in years. TDEE multiplies BMR by 1.2 (sedentary) up to ~1.9 (very active). A daily deficit of 500 kcal produces roughly 0.45 kg / 1 lb of weight loss per week.
Worked example
A 30-year-old man weighing 80 kg at 180 cm: BMR = 10×80 + 6.25×180 − 5×30 + 5 = 1,780 kcal. Moderately active (×1.55), his TDEE is about 2,759 kcal. For weight loss at a 500 kcal deficit, the target is ~2,259 kcal per day.
Frequently asked questions
How many calories should I eat to lose weight?
Subtract a moderate deficit (typically 300–500 kcal) from your TDEE. Larger deficits cause faster loss but are harder to sustain and can reduce lean mass.
What is TDEE?
Total Daily Energy Expenditure is the number of calories you burn in a day, including your basal metabolic rate plus activity, digestion and exercise.
Which calorie formula is most accurate?
For most healthy adults the Mifflin–St Jeor equation is more accurate than the older Harris–Benedict formula. Direct measurement (indirect calorimetry) is the gold standard.