How the calorie calculator works
Your daily calorie needs come from two parts.
1. Basal metabolic rate (BMR). The energy your body uses at complete rest. We use the Mifflin-St Jeor equation:
- Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
- Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
2. Activity. BMR is multiplied by an activity factor to get your TDEE, your maintenance calories:
- Sedentary: 1.2
- Light exercise (1–3 days/week): 1.375
- Moderate (3–5 days/week): 1.55
- Very active (6–7 days/week): 1.725
- Athlete or physical job: 1.9
From your TDEE, the calculator shows targets for mild, standard and faster fat loss, maintenance, and lean or standard gain.
Choosing the right target
- Fat loss: start with about 500 kcal below maintenance. It’s enough to see progress without feeling drained.
- Muscle gain: a small surplus of 250 kcal limits fat gain. Beginners can build muscle even at maintenance.
- Recomposition: if you’re new to lifting, eating at maintenance with high protein can lose fat and build muscle at the same time.
Most people overestimate their activity level. If you’re unsure between two levels, pick the lower one.
Make the number work in real life
- Track for two to three weeks. Weigh yourself in the morning and look at the weekly average, not single days.
- Adjust by 100–200 kcal if your weight isn’t moving in the right direction after two to three weeks.
- Split your calories into macros with the macro calculator, so you get enough protein.
- Turn it into meals with the meal plan generator.
Limitations
Calorie equations are estimates for healthy adults. They’re less accurate for very muscular or very overweight people, during pregnancy, and with conditions such as thyroid disorders. If that’s you, a dietitian consultation gives you a personalised target.
