Health & Fitness

Calorie Calculator – TDEE, Macros & Weight Goal Timeline

Calculate your Total Daily Energy Expenditure (TDEE), Basal Metabolic Rate (BMR), and a full macro split (protein, carbs, fat) tailored to your goal. Includes a weight loss or gain timeline showing when you'll reach your target.

Based on Mifflin-St Jeor equation · NHS-aligned guidance

What Is TDEE and Why Does It Matter?

Your Total Daily Energy Expenditure is the total number of calories your body burns in a day — at rest plus through activity. Eating at your TDEE maintains your current weight. Eating below it creates a deficit and causes fat loss. Eating above it creates a surplus and causes weight gain (muscle or fat depending on training and protein intake).

A calorie deficit of 500 kcal/day typically produces around 0.5 kg of weight loss per week (since 1 kg of body fat contains approximately 7,700 kcal). Going too aggressive — more than 1,000 kcal below TDEE — risks muscle loss, fatigue, and nutrient deficiencies. A sustainable rate is 0.5–1 kg/week.

Macronutrients Explained

Your daily calories come from three macronutrients: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). The right balance depends on your goal:

NHS minimum calorie guidance: NHS advises against eating below 1,200 kcal/day for women or 1,500 kcal/day for men without medical supervision. Very low calorie diets (800 kcal/day) should only be undertaken under clinical guidance and for a limited period.