Your Personalized Weight Loss Nutrition Calculator
Enter your current body weight in kilograms.
Enter your height in centimeters.
Enter your age in whole years.
Male
Female
Select your gender for more accurate calculations.
Sedentary (little or no exercise)
Lightly active (light exercise/sports 1-3 days/week)
Moderately active (moderate exercise/sports 3-5 days/week)
Very active (hard exercise/sports 6-7 days a week)
Extra active (very hard exercise/sports & physical job)
Choose the option that best describes your lifestyle.
Enter your target weight in kilograms.
Enter how much weight you aim to lose each week (e.g., 0.5 kg).
Your Weight Loss Nutrition Plan
— kcal/day
Basal Metabolic Rate (BMR): — kcal/day
Total Daily Energy Expenditure (TDEE): — kcal/day
Target Daily Calorie Intake: — kcal/day
How it's calculated: We first estimate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, then multiply by your activity level to find your Total Daily Energy Expenditure (TDEE). Finally, we subtract calories for your desired weekly weight loss to determine your target daily intake. A deficit of 3500 kcal is roughly equivalent to 0.5 kg of fat loss.
Daily Calorie Needs vs. Target Intake
Metric
Value
Unit
Current Weight
—
kg
Height
—
cm
Age
—
Years
Gender
—
–
Activity Level
—
–
Goal Weight
—
kg
Weekly Loss Goal
—
kg/week
BMR
—
kcal/day
TDEE (Maintenance)
—
kcal/day
Target Intake (for loss)
—
kcal/day
Estimated Weeks to Goal
—
Weeks
What is Calculating What to Eat to Lose Weight?
Calculating what to eat to lose weight involves understanding your body's energy needs and creating a calorie deficit through mindful food choices and portion control. It's not about restrictive fad diets, but rather a sustainable approach to nutrition that supports your weight loss goals while ensuring you receive adequate nutrients. This process typically begins with determining your Basal Metabolic Rate (BMR) – the calories your body burns at rest – and your Total Daily Energy Expenditure (TDEE), which accounts for your activity level. By establishing a calorie deficit from your TDEE, you can effectively encourage your body to use stored fat for energy, leading to weight loss.
This method is suitable for almost anyone looking to achieve a healthier weight in a structured and informed way. Whether you're aiming to shed a few pounds or a significant amount of weight, understanding your caloric requirements is fundamental.
A common misconception is that weight loss solely depends on drastically cutting calories, often leading to unsustainable and unhealthy eating patterns. Another is that all calories are created equal; in reality, the nutritional quality of your food significantly impacts satiety, energy levels, and overall health, even within a calorie deficit. Effective weight loss is a blend of sufficient calorie reduction and nutrient-dense food selection.
Weight Loss Calorie Calculation Formula and Explanation
The core of calculating what to eat to lose weight lies in creating an energy deficit. The most common method involves estimating your Total Daily Energy Expenditure (TDEE) and then reducing your intake below this level.
Step 1: Calculate Basal Metabolic Rate (BMR)
We use the Mifflin-St Jeor equation, considered one of the most accurate for estimating BMR:
For Men: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
For Women: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Step 2: Calculate Total Daily Energy Expenditure (TDEE)
TDEE is your BMR multiplied by an activity factor that reflects your lifestyle.
TDEE = BMR × Activity Factor
The activity factors used are:
Sedentary: 1.2
Lightly active: 1.375
Moderately active: 1.55
Very active: 1.725
Extra active: 1.9
Step 3: Determine Target Calorie Intake for Weight Loss
To lose weight, you need to consume fewer calories than your TDEE. A common guideline is that a deficit of approximately 3,500 calories leads to the loss of about 0.45 kg (1 pound) of fat. To achieve a specific weekly weight loss goal, we can calculate the required daily deficit.
Daily Calorie Deficit = Desired Weekly Weight Loss (kg) × 1100 (approx. kcal per kg of fat)
Note: We use 1100 kcal/kg as a common estimate for fat tissue energy content, which translates to roughly 7700 kcal for 0.7kg, or about 3500 kcal per pound. This calculation simplifies to ~1100 kcal deficit per 0.1kg of desired weekly loss.
Step 4: Calculate Estimated Time to Reach Goal Weight
This estimates how long it might take to reach your goal, assuming consistent adherence to the target calorie intake.
Total Weight to Lose (kg) = Current Weight – Goal Weight
Estimated Weeks to Goal = Total Weight to Lose (kg) / Desired Weekly Weight Loss (kg/week)
Variables Table
Variable
Meaning
Unit
Typical Range
Current Weight
Your current body mass.
Kilograms (kg)
30 – 300+
Height
Your vertical body mass.
Centimeters (cm)
100 – 220
Age
Your chronological age.
Years
5 – 120
Gender
Biological sex, affecting metabolic rate.
Male/Female
–
Activity Level
Multiplier reflecting daily physical activity.
Factor (e.g., 1.2 – 1.9)
1.2 – 1.9
Goal Weight
Your target body mass.
Kilograms (kg)
20 – 300+
Desired Weekly Weight Loss
How fast you aim to lose weight.
Kilograms per week (kg/week)
0.1 – 2.0
BMR
Calories burned at rest.
Kilocalories per day (kcal/day)
800 – 2500+
TDEE
Total calories burned daily, including activity.
Kilocalories per day (kcal/day)
1200 – 4000+
Target Daily Calorie Intake
Recommended calorie consumption for weight loss.
Kilocalories per day (kcal/day)
1000 – 3000+
Estimated Weeks to Goal
Timeframe to reach target weight.
Weeks
1 – 100+
Practical Examples of Calculating What to Eat to Lose Weight
Understanding the calculations in practice can demystify the process. Here are a couple of examples:
Example 1: Moderately Active Woman aiming for gradual loss
Sarah is a 35-year-old woman, currently weighing 75 kg, standing 165 cm tall. She considers herself moderately active, exercising 3-4 times a week. Her goal weight is 65 kg, and she aims for a sustainable loss of 0.5 kg per week.
Inputs: Current Weight: 75 kg, Height: 165 cm, Age: 35, Gender: Female, Activity Level: Moderately active (1.55), Goal Weight: 65 kg, Weekly Loss Rate: 0.5 kg/week.
Estimated Weeks to Goal = 10 kg / 0.5 kg/week = 20 weeks
Interpretation: To achieve her goal, Sarah should aim for approximately 1690 calories per day. This intake supports her activity level while creating a deficit for consistent weight loss over about 20 weeks. She should focus on nutrient-dense foods to feel full and satisfied within this calorie budget.
Example 2: Sedentary Man wanting to lose weight faster
Mark is a 48-year-old man, weighing 90 kg and standing 180 cm tall. His job is largely desk-bound, making him sedentary. He wants to reach 80 kg and is willing to aim for a quicker loss of 1 kg per week.
Inputs: Current Weight: 90 kg, Height: 180 cm, Age: 48, Gender: Male, Activity Level: Sedentary (1.2), Goal Weight: 80 kg, Weekly Loss Rate: 1.0 kg/week.
Estimated Weeks to Goal = 10 kg / 1.0 kg/week = 10 weeks
Interpretation: Mark needs to consume around 1050 calories per day. This is a significant deficit, and while it aims for faster results (10 weeks), it's crucial for Mark to ensure he's still getting adequate nutrition and listen to his body. A deficit this large might be challenging and could benefit from professional guidance.
How to Use This Weight Loss Nutrition Calculator
Enter Your Current Stats: Input your current weight, height, age, and gender accurately. These are the foundational metrics for calculating your metabolic rate.
Select Your Activity Level: Choose the option that best describes your daily physical activity. This significantly impacts your total calorie needs.
Set Your Weight Loss Goals: Enter your desired goal weight and the rate at which you wish to lose weight per week. Be realistic; a loss of 0.5 kg to 1 kg per week is generally considered safe and sustainable for most individuals.
Click 'Calculate': The calculator will immediately provide your estimated BMR, TDEE, and your target daily calorie intake for weight loss.
Interpret the Results:
Target Daily Calorie Intake: This is the primary number to guide your eating. Plan your meals to stay around this calorie target.
BMR & TDEE: Understanding these helps you see how many calories your body burns naturally versus with activity.
Estimated Weeks to Goal: This gives you a realistic timeframe, helping to manage expectations.
Use the Data: The table provides a summary of all inputs and calculated values. The chart visually represents your maintenance calories versus your target intake. Use this information to plan balanced meals rich in nutrients.
Reset Option: If you need to recalculate with different inputs, click the 'Reset' button to return to default values or clear your previous entries.
Copy Results: The 'Copy Results' button allows you to easily save or share your calculated plan.
Decision Guidance: Aim for nutrient-dense foods (vegetables, fruits, lean proteins, whole grains) to maximize satiety and nutritional value within your target calorie intake. If your target calorie intake seems excessively low (e.g., below 1200 kcal/day), consult a healthcare professional or registered dietitian to ensure safety and adequacy of nutrients.
Key Factors That Affect Weight Loss Calculations
While our calculator provides a strong estimate, several factors can influence your actual weight loss journey and caloric needs. Understanding these can help you adjust your approach for better results.
Body Composition: Muscle tissue burns more calories at rest than fat tissue. Someone with a higher muscle mass might have a higher BMR than their weight alone suggests.
Metabolic Adaptations: As you lose weight, your BMR and TDEE naturally decrease. Your body may also become more efficient at conserving energy, a phenomenon known as metabolic adaptation, which can slow down weight loss over time.
Hormonal Factors: Hormones like thyroid hormones, cortisol, and sex hormones play a significant role in metabolism and appetite regulation. Imbalances can impact weight loss efforts.
Genetics: Individual genetic predispositions can influence metabolism, fat storage, and appetite.
Sleep Quality: Poor sleep can disrupt hormones that regulate appetite (ghrelin and leptin), potentially increasing hunger and cravings, and impairing metabolic function.
Stress Levels: Chronic stress can lead to elevated cortisol levels, which may promote fat storage, particularly around the abdomen, and increase cravings for high-calorie foods.
Medications: Certain medications can affect metabolism, appetite, or fluid balance, influencing weight.
Dietary Adherence and Accuracy: Consistently sticking to your calorie target and accurately tracking your intake are crucial. Errors in portion estimation or tracking can lead to a different actual deficit than planned.
Frequently Asked Questions (FAQ)
Q1: Is a calorie deficit the only way to lose weight?
A: While a calorie deficit is the fundamental principle of weight loss (consuming fewer calories than you burn), the *composition* of your diet matters greatly. Focusing on nutrient-dense, whole foods can improve satiety, provide essential vitamins and minerals, and support overall health during weight loss, making the deficit more sustainable and less likely to cause nutrient deficiencies. Exercise also plays a crucial role in increasing calorie expenditure and improving body composition.
Q2: Can I lose 2 kg per week?
A: Losing 2 kg per week requires a very large calorie deficit (approximately 2200 kcal per day). While possible for individuals with very high starting TDEE, it is often unsustainable, can lead to muscle loss, nutrient deficiencies, and is generally not recommended for long-term health. A safer and more sustainable rate is typically 0.5-1 kg per week.
Q3: What if my target calorie intake is very low?
A: If your calculated target daily calorie intake falls below 1200 kcal (for women) or 1500 kcal (for men), it's advisable to consult a healthcare professional or a registered dietitian. Such low intakes can make it difficult to obtain adequate nutrients and may not be sustainable. They can help you create a safer, more effective plan.
Q4: How accurate is the Mifflin-St Jeor equation?
A: The Mifflin-St Jeor equation is generally considered one of the most accurate predictive equations for BMR currently available. However, it is still an estimate. Individual metabolic rates can vary due to genetics, body composition, and other factors.
Q5: Should I focus on macronutrient percentages or total calories?
A: For weight loss, achieving the correct calorie deficit is paramount. Once your calorie target is set, focusing on macronutrient balance (protein, carbohydrates, fats) becomes important for satiety, muscle preservation, and overall health. Many find a higher protein intake beneficial for feeling full.
Q6: How does exercise affect my calorie needs?
A: Exercise increases your TDEE. If you increase your activity level, your maintenance calorie needs go up. To maintain a calorie deficit for weight loss, you would need to either increase your food intake slightly to match the new TDEE, or maintain your original target intake to create an even larger deficit. Our calculator incorporates activity level directly.
Q7: Will my metabolism slow down permanently from dieting?
A: Prolonged or extreme calorie restriction can lead to metabolic adaptations where your metabolism slows down. However, for most people, this is reversible. Implementing periods of normal calorie intake, strength training, and ensuring adequate protein can help mitigate and reverse metabolic slowdown.
Q8: How important is hydration for weight loss?
A: Staying well-hydrated is crucial for weight loss. Water supports metabolism, can help with feelings of fullness, and is essential for all bodily functions. Sometimes thirst can be mistaken for hunger, so drinking water throughout the day can help manage appetite.