How to Use the Calorie & Macro Calculator
- Enter your age, sex, height and weight.
- Select your activity level.
- Choose your goal: lose, maintain or gain.
- See your daily calorie target and macro breakdown.
How calorie needs are estimated
Daily calorie needs are usually estimated in two steps: your basal metabolic rate (the energy your body uses at rest), then a multiplier for how active you are, giving your total daily energy expenditure. Widely used formulas like Mifflin-St Jeor base the estimate on your age, sex, height and weight.
The result is a solid starting estimate, not an exact measurement, since real needs vary between individuals.
Using the number sensibly
To lose weight you generally aim to eat somewhat below your daily need, and to gain, somewhat above, with gradual changes being the most sustainable. Very large deficits are hard to maintain and can backfire.
This is general information, not medical or dietary advice. If you have health conditions or specific goals, check with a doctor or a registered dietitian before making big changes.
Frequently Asked Questions
How are my calorie needs calculated?
The tool calculates your Basal Metabolic Rate with the Mifflin-St Jeor equation, multiplies it by an activity factor to get your Total Daily Energy Expenditure (TDEE), then adjusts for your goal.
How are the macros split?
Protein is set from your body weight, fat from a share of total calories, and the remainder goes to carbohydrates. You can treat these as a sensible starting point.
Is this medical advice?
No. These are general estimates. Consult a doctor or registered dietitian before making significant changes to your diet, especially with health conditions.