| Goal | Calories/day |
|---|---|
Mild weight loss (−250/day) about 0.25 kg / 0.5 lb per week | 2,306 kcal |
Weight loss (−500/day) about 0.5 kg / 1 lb per week | 2,056 kcal |
Mild weight gain (+250/day) about 0.25 kg / 0.5 lb per week | 2,806 kcal |
Weight gain (+500/day) about 0.5 kg / 1 lb per week | 3,056 kcal |
Estimates only, not medical advice.
How to use the Calorie Calculator
- 1Select your sex and choose Metric or Imperial units.
- 2Enter your age, height and current weight.
- 3Pick the activity level that best matches a typical week.
- 4Read your maintenance calories (TDEE) and your basal metabolic rate (BMR).
- 5Use the goals table to see daily targets for mild or standard weight loss and gain.
How your calorie needs are calculated
The first step is your basal metabolic rate (BMR), the energy your body uses at complete rest to breathe, circulate blood and keep organs working. The Mifflin-St Jeor equation estimates it as 10 × weight in kg + 6.25 × height in cm − 5 × age in years, plus 5 for men or minus 161 for women.
BMR is then multiplied by an activity factor to give your total daily energy expenditure (TDEE), also called maintenance calories. The factors used here are 1.2 for sedentary, 1.375 for lightly active, 1.55 for moderately active, 1.725 for very active and 1.9 for extra active. Eating close to your TDEE should keep your weight roughly stable.
Worked example
Take a 30-year-old man who is 175 cm tall, weighs 70 kg and exercises three to five days a week. His BMR is 10 × 70 + 6.25 × 175 − 5 × 30 + 5 = 1,648.75, or about 1,649 kcal. Multiplying by 1.55 gives a TDEE of about 2,556 kcal per day.
His targets are then about 2,306 kcal for mild weight loss, 2,056 kcal for weight loss, 2,806 kcal for mild weight gain and 3,056 kcal for weight gain. A 35-year-old woman who is 165 cm, 60 kg and lightly active has a BMR of about 1,295 kcal and a TDEE of about 1,781 kcal.
Calories for weight loss and weight gain
A common rule of thumb is that a deficit of about 500 kcal a day leads to roughly 0.5 kg (1 lb) of weight loss per week, and 250 kcal a day to about half that. The same logic applies in reverse for gaining weight. Real results vary, because metabolism adapts and water weight fluctuates, so use the numbers as a starting point and adjust after a few weeks based on how your weight actually changes.
Very low intakes are hard to sustain and can make it difficult to get enough protein, vitamins and minerals. The calculator shows a note if a target falls below about 1,200 kcal for women or 1,500 kcal for men. To see whether your current weight is in a healthy range, try the BMI calculator.
Estimates, not medical advice
Any formula gives an estimate for an average person. Your true needs depend on muscle mass, genetics, health conditions, medications and how accurately you judge your activity level; most people overestimate it. Mifflin-St Jeor is usually within about 10% of measured values for most adults, but individual errors can be larger.
These results are not medical advice. If you are pregnant, breastfeeding, under 18, managing a medical condition or planning a large change in weight, speak to a doctor or registered dietitian. Body composition matters too, and the body fat calculator can help you track fat loss rather than just weight.
Learn more
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is the energy you would burn lying at rest all day. TDEE adds the energy used for daily movement and exercise, so it is always higher. TDEE is the figure to use when planning how much to eat.
Which activity level should I choose?
Pick the level that matches a typical week, not your best week. If you have a desk job and exercise two or three times a week, lightly active is usually more accurate than moderately active. When in doubt, choose the lower option.
Why does the calculator ask for my sex?
At the same height, weight and age, men usually have more muscle and a higher resting energy use. The Mifflin-St Jeor equation reflects this with a different constant: plus 5 for men and minus 161 for women.
How accurate is this calorie calculator?
It is a reasonable starting estimate for most healthy adults, but no equation can measure your metabolism directly. Track your weight for two to four weeks and adjust your intake by 100 to 200 kcal if it is not moving as expected.
Do I need to drink more water when I exercise more?
Yes. Fluid needs rise with activity and heat, just as calorie needs do. The water intake calculator estimates a daily target that accounts for exercise and climate.