Calorie calculation7 min read
How to Calculate Your Daily Calories: A Practical Guide
Calorie needs are not one fixed number for everyone. The estimate starts with the energy your body uses at rest, then changes with activity and your goal. Here is a clear way to understand—and use—the number from a calorie calculator.
1. Start with resting energy needs
Mem uses the Mifflin–St Jeor equation to estimate resting energy expenditure. It uses weight in kilograms, height in centimetres, age, and the sex term used by the equation.
The equation comes from published research, but it remains a statistical estimate—not a direct measurement of your metabolism.
Men
(10 × weight) + (6.25 × height) − (5 × age) + 5
Women
(10 × weight) + (6.25 × height) − (5 × age) − 161
Example: Man, 80 kg, 175 cm, 30 years. (10 × 80) + (6.25 × 175) − (5 × 30) + 5 = 1,749
2. Adjust for your activity
Resting expenditure does not represent your whole day. A selected activity level is used to estimate total daily needs.
Choose the level that reflects your average week, not your single busiest day. Overestimating activity is a common reason calorie targets start too high.
- Sedentary: desk-based days with limited movement.
- Light: some movement or light training during the week.
- Moderate: regular training or an active occupation.
- High: demanding training or physical work on most days.
3. Match calories to your goal
Maintenance calories are the estimated starting point for stable weight. For weight loss, a conservative change is generally easier to sustain than an aggressive cut. For gain, gradual additions make the response easier to monitor.
Do not change calories every day because the scale moved. Review average weight, adherence, and energy over two to four weeks before adjusting, unless a qualified professional advises otherwise.
4. From rest to a daily target
The 1,749 figure in the example above is resting energy only. Total daily needs become higher after activity is considered.
This example only demonstrates the calculation. A useful real-world target also depends on input accuracy, activity, body composition, health, and the response over time.
5. When a calculator is not enough
A calculator is an educational tool, not a diagnosis or treatment plan. Consult a physician or credentialed dietitian if you are pregnant or breastfeeding, under 18, have an eating disorder, or have a condition or medication that affects weight, appetite, or metabolism.
Prefer a personalised result?
Use the calculator for an estimate based on your measurements, activity, and goal.
Calculate your caloriesSources
Prepared by the Mem Nutrition editorial team and not yet reviewed by a credentialed dietitian. Educational content only. It does not replace individual medical advice. Read the nutrition disclaimer.