How many calories does your body need?
Your body needs energy for vital functions such as breathing, circulation and keeping warm, plus energy for movement and exercise. That energy is measured in calories (kcal). Eat more than you burn and you gain weight; eat less and you lose it. Knowing your daily needs is the first step in any successful nutrition plan.
How we calculate it
1. Basal Metabolic Rate (BMR)
The calories your body burns at complete rest. We use the Mifflin–St Jeor equation, considered the most accurate for adults by dietetic associations:
- Men:
10 × weight + 6.25 × height − 5 × age + 5 - Women:
10 × weight + 6.25 × height − 5 × age − 161
2. Total Daily Energy Expenditure (TDEE)
BMR is multiplied by an activity factor from 1.2 (sedentary) to 1.9 (very hard physical activity). The result is the calories needed to maintain your weight.
Losing weight healthily
One kilogram of body fat holds roughly 7,700 kcal (about 3,500 kcal per pound). A daily deficit of 500 kcal leads to about 0.5 kg (1 lb) of loss per week — the pace most doctors recommend. Going below 1,200 kcal/day for women or 1,500 for men without medical supervision isn't advised, as it can cause nutrient deficiencies, muscle loss and a slower metabolism.
Macronutrient split
- Protein (30%): preserves muscle and keeps you full — chicken, fish, eggs, legumes, dairy.
- Carbohydrates (40%): your main energy source — choose whole grains, vegetables and fruit.
- Fat (30%): essential for hormones — favor olive oil, nuts and avocado.
Protein and carbs provide 4 kcal per gram; fat provides 9. Also check your BMI and daily water needs.
⚕️ Results are estimates for healthy adults. Pregnant or breastfeeding women and people with diabetes, thyroid or other conditions should follow a plan from a doctor or dietitian.
Frequently Asked Questions
How many calories should I eat to lose weight?
Subtract about 500 kcal from your TDEE to lose roughly 0.5 kg (1 lb) per week, without going below the safe minimum.
What's the difference between BMR and TDEE?
BMR is what you burn at complete rest; TDEE is your total daily burn including activity.
How accurate is it?
Mifflin–St Jeor is accurate within about 10% for most people. Track your weight for two weeks and adjust.
Do I need to count calories exactly?
Not necessarily — a ballpark figure helps with portions; food quality and consistency matter most.
Is my data saved?
No. Everything is calculated in your browser.
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