How Many Calories Should You Eat to Lose Weight?

Estimate your daily calorie target to lose weight based on your age, height, weight, activity level, and goal. Free & instant.

About this tool

Understanding how many calories you need to eat to lose weight is one of the most practical steps you can take on your health journey. At its core, weight loss is driven by a **calorie deficit** — consuming fewer calories than your body burns each day. This calculator helps you estimate a personalized daily calorie target based on your unique body measurements, lifestyle, and goals. The calculation starts with your **Basal Metabolic Rate (BMR)**, which represents the number of calories your body needs just to maintain basic functions like breathing, circulation, and cell repair while at complete rest. This tool uses the Mifflin-St Jeor equation, one of the most widely referenced formulas in nutrition science, to estimate BMR from your weight, height, and age. Once your BMR is calculated, it is multiplied by an **activity multiplier** that reflects how physically active you are in daily life. Someone with a desk job who rarely exercises will have a lower total energy expenditure than someone who works out intensely most days of the week. This adjusted figure is called your **Total Daily Energy Expenditure (TDEE)** — the total calories you burn in a typical day. To lose weight, you need to eat fewer calories than your TDEE. Approximately 1 kg of body fat contains roughly 7,700 kilocalories of stored energy. So to lose 0.5 kg per week, you would need a daily deficit of around 550 kcal; to lose 1.0 kg per week, a deficit of roughly 1,100 kcal. This calculator subtracts the appropriate deficit from your TDEE based on your selected weekly goal. It is important to remember that these figures are **estimates**, not medical prescriptions. Individual metabolism varies due to genetics, hormonal factors, sleep quality, stress, and other elements that no single formula can fully capture. The numbers provided here are a useful starting point for planning, but results in real life may differ. If your calculated target falls very low (for example, below around 1,200 kcal for women or 1,500 kcal for men), it is generally advisable to consult a registered dietitian or healthcare professional before proceeding, as extremely low intake can impact nutrition and overall health. For sustainable results, most nutrition experts suggest aiming for a moderate deficit — typically 0.5 kg per week — rather than aggressive restriction. Rapid weight loss can lead to muscle loss, nutrient deficiencies, and is often harder to maintain long-term. Pairing a calorie-conscious diet with regular physical activity tends to produce better and more lasting outcomes than diet alone. Use this calculator as a practical guide to set a realistic daily calorie goal, track your progress over several weeks, and adjust as needed based on how your body responds.

FAQ

Q. What is a calorie deficit and why does it cause weight loss?
A. A calorie deficit occurs when you consume fewer calories than your body burns in a day. Since your body needs energy to function, it compensates by drawing on stored fat for fuel, which gradually leads to weight loss over time. The larger the deficit, the faster the potential weight loss — though very large deficits are generally not recommended for long-term health.
Q. How accurate is this calorie calculator?
A. This calculator uses the Mifflin-St Jeor equation, which is widely considered one of the more accurate formulas for estimating calorie needs in average adults. However, it is still an estimate. Factors like muscle mass, hormonal health, gut microbiome, and sleep can all affect actual calorie needs. Treat the result as a helpful starting point and adjust based on real-world results over 2–4 weeks.
Q. Is it safe to eat at a large calorie deficit to lose weight faster?
A. Eating at a very large calorie deficit can cause rapid weight loss in the short term, but it often comes with downsides such as muscle loss, fatigue, nutritional deficiencies, and difficulty sustaining the approach. Most health guidelines suggest a moderate deficit that targets around 0.5–1.0 kg of weight loss per week as a safer and more sustainable range for most people.
Q. Do I need to change my calorie target as I lose weight?
A. Yes. As your body weight decreases, your BMR and TDEE also decrease, meaning you burn fewer calories at rest and during activity. This is why weight loss can slow down over time even if your diet hasn't changed. Recalculating your target every few weeks and adjusting accordingly is a common strategy to keep progressing toward your goal.
Q. Should I focus only on calories, or do macronutrients matter too?
A. Calories are the primary driver of weight change, but the composition of those calories — protein, carbohydrates, and fats — also matters for body composition, satiety, and overall health. Eating adequate protein, for example, can help preserve muscle mass during a calorie deficit. For general weight loss purposes, starting with a calorie target is a solid first step, and refining macronutrient balance can be a useful next layer of optimization.

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