Calorie Calculator
Calculate your daily calorie needs based on your lifestyle and reach your weight goals with a personalised plan.
| Activity Level | Daily Calories | Weekly Calories |
|---|---|---|
| Enter details above | ||
Find out how many calories you need each day to lose, maintain, or gain weight, based on your body stats, activity level, and the Mifflin-St Jeor equation.
How Calorie Calculator Works
The calculator first estimates your Basal Metabolic Rate (BMR) — the energy your body burns at complete rest — using the Mifflin-St Jeor equation: for men, BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5, and for women, the same formula minus 161 instead of plus 5. Imperial entries are converted to kilograms and centimeters before the formula is applied.
BMR is then multiplied by an activity factor ranging from 1.2 (sedentary) to 1.9 (extra active, physically demanding job plus hard training) to produce your Total Daily Energy Expenditure (TDEE) — the calories you burn in an average day including movement and exercise.
Your selected goal simply shifts that TDEE up or down: −500 calories/day for roughly 1 lb of weekly loss, −1,000 for about 2 lbs, or the mirror-image adjustments for weight gain. The suggested macro split (30% protein, 40% carbs, 30% fat) is then applied to your goal calories to produce gram targets for each macronutrient.
See It In Action
Who Uses Calorie Calculator and Why
- Setting a starting daily calorie target before beginning a weight-loss or weight-gain plan.
- Figuring out roughly how many calories to eat to maintain your current weight during a maintenance phase.
- Getting a starting protein/carb/fat gram breakdown to plan meals around, rather than just a total calorie number.
Mistakes to Avoid
- Choosing an activity level that overstates your real week — picking "very active" because you work out a few times, when your job and daily life are otherwise sedentary, inflates your TDEE and the resulting calorie target.
- Expecting the scale to move exactly on schedule — the −500/−1,000 calorie adjustments are estimates, and week-to-week weight includes water and other fluctuations, not just fat loss.
- Treating the 30/40/30 macro split as mandatory rather than a reasonable default that can be adjusted to personal preference or a specific diet style.
Tips for Best Results
- Re-run the calculator every 10–15 lbs of weight change, since your BMR shifts as your weight does and the original target will gradually become less accurate.
- If your weight isn't tracking as expected after two to three weeks at your target, adjust by 100–200 calories based on the real trend rather than assuming the formula got something wrong.
Fixing Common Problems
I'm eating my target calories but not losing weight. — Give it two to three full weeks to see a genuine trend rather than day-to-day fluctuation, then check your food logging accuracy — small underestimates of portion size add up. If the trend is still flat, shift down by 100–200 calories.
My result looks very different from another calculator I tried. — Other tools may use Harris-Benedict or Katch-McArdle instead of Mifflin-St Jeor, or assume a different activity multiplier — check which formula the other tool used before assuming either result is wrong.
Terms Explained
TDEE (Total Daily Energy Expenditure): Your BMR multiplied by an activity factor — the total calories you burn in a typical day including movement and exercise.
Activity factor: A multiplier from 1.2 (sedentary) to 1.9 (extra active) applied to BMR to estimate real-world daily calorie burn.