Daily Calorie Needs (TDEE) Calculator

Understanding your daily calorie needs is a useful starting point for weight management, energy levels, and general wellbeing. This calculator estimates both your BMR (resting energy needs) and your TDEE (total daily energy needs, including activity).

How This Is Calculated

Your BMR is estimated using the Mifflin-St Jeor equation, one of the most widely used and well-validated formulas in nutrition science:

• Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
• Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161

Your TDEE is then calculated by multiplying your BMR by an activity factor: 1.2 for sedentary, 1.375 for lightly active (1–3 days/week), 1.55 for moderately active (3–5 days/week), 1.725 for active (6–7 days/week), or 1.9 for very active (a physical job, or training twice a day).

When Calorie Needs Change

Calorie needs are not fixed for life — they shift with age, hormonal changes, medication, and activity levels. This is particularly relevant during menopause, when hormonal changes and age-related muscle loss can lower resting energy needs; I cover this in more detail in my guide to menopause and weight gain. Calorie needs are also an important consideration for anyone using GLP-1 medicationssuch as Ozempic or Mounjaro, where appetite changes can make it easy to under-eat certain nutrients even as total calorie intake falls — see my article on GLP-1, weight loss and nutrition.

Frequently Asked Questions

This calculator provides general information only and is not medical advice. It is not a substitute for individual clinical assessment. Please speak to your GP or a registered dietitian about any concerns regarding your weight, health, or medication.