Calculate your ideal daily calorie intake to achieve your weight loss goals safely and effectively.
Male
Female
Select your biological sex.
Enter your age in years.
Please enter a valid age (1-120).
Enter your current weight in kilograms (kg).
Please enter a valid weight (1-1000 kg).
Enter your height in centimeters (cm).
Please enter a valid height (30-250 cm).
Sedentary (little to 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 daily activity.
0.25 kg (0.5 lbs) per week
0.5 kg (1 lb) per week (Recommended)
0.75 kg (1.5 lbs) per week
1.0 kg (2 lbs) per week (Maximum Recommended)
Select your target rate of weight loss. A rate of 0.5 kg (1 lb) per week is generally considered safe and sustainable.
Your Weight Loss Calorie Targets
— kcal
—
Basal Metabolic Rate (BMR)
—
Total Daily Energy Expenditure (TDEE)
—
Daily Calorie Deficit
Calculated using the Mifflin-St Jeor Equation for BMR and factoring in activity level and weight loss goals.
Calorie Intake vs. Expenditure Over Time
Estimated daily calorie intake required to meet your weight loss goal, compared to your estimated TDEE.
Practical Examples
Here are a couple of examples to illustrate how the calculator works:
Example 1: Sarah, aiming for moderate weight loss
Input
Value
Biological Sex
Female
Age
32
Weight
75 kg
Height
165 cm
Activity Level
Moderately Active (1.55)
Desired Weekly Weight Loss
0.5 kg/week
Output
Result
Basal Metabolic Rate (BMR)
1480 kcal
Total Daily Energy Expenditure (TDEE)
2294 kcal
Daily Calorie Deficit
500 kcal
Target Daily Calorie Intake (Weight Loss)
1794 kcal
Example 2: Mark, very active, aiming for faster loss
Input
Value
Biological Sex
Male
Age
45
Weight
90 kg
Height
180 cm
Activity Level
Very Active (1.725)
Desired Weekly Weight Loss
1.0 kg/week
Output
Result
Basal Metabolic Rate (BMR)
1845 kcal
Total Daily Energy Expenditure (TDEE)
3183 kcal
Daily Calorie Deficit
1000 kcal
Target Daily Calorie Intake (Weight Loss)
2183 kcal
What is the Calories to Eat to Lose Weight Calculation?
The "Calories to Eat to Lose Weight Calculator" is a vital tool for anyone looking to manage their weight. It helps determine the specific daily calorie intake required to create a sustainable energy deficit, leading to gradual and healthy weight loss. By inputting personal details such as age, sex, weight, height, and activity level, the calculator estimates your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). It then adjusts this figure based on your desired weekly weight loss to provide a personalized calorie target.
Who should use it? Anyone aiming to lose weight safely and effectively. This includes individuals looking to shed a few pounds or those embarking on a more significant weight loss journey. It's particularly useful for those who want to avoid overly restrictive diets and aim for a balanced approach to calorie intake.
Common misconceptions: A common misconception is that all calories are equal, regardless of source. While the calculator provides a numerical target, the *quality* of those calories (from nutrient-dense foods vs. processed foods) significantly impacts health, satiety, and overall well-being. Another misconception is that very low-calorie diets are always best for rapid weight loss; however, these can be unsustainable, lead to muscle loss, and negatively affect metabolism.
Calories to Eat to Lose Weight Formula and Mathematical Explanation
The calculation typically involves two main steps: estimating your energy needs at rest (BMR) and then factoring in your activity level to determine your total daily energy expenditure (TDEE). Finally, a deficit is created for weight loss.
Step 1: Basal Metabolic Rate (BMR) Calculation
The most widely accepted formula for BMR is the Mifflin-St Jeor equation. It's considered more accurate than the older Harris-Benedict equation for most individuals.
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: Total Daily Energy Expenditure (TDEE) Calculation
TDEE is calculated by multiplying your BMR by an activity factor that reflects your daily physical activity level.
TDEE = BMR × Activity Factor
Activity Factors:
Sedentary (little or no exercise): 1.2
Lightly Active (light exercise/sports 1-3 days/week): 1.375
Moderately Active (moderate exercise/sports 3-5 days/week): 1.55
Very Active (hard exercise/sports 6-7 days/week): 1.725
Extra Active (very hard exercise/sports & physical job): 1.9
Step 3: Calorie Target for Weight Loss
To lose weight, you need to consume fewer calories than your TDEE, creating a calorie deficit. A common guideline is that a deficit of approximately 3500 calories results in about 0.5 kg (1 lb) of fat loss.
Daily Calorie Deficit = Desired Weekly Weight Loss (kg) × 7700 kcal/kg (approx. 1100 kcal/day for 1kg/week loss, or 550 kcal/day for 0.5kg/week loss)
Calories burned at complete rest to maintain basic bodily functions.
Kilocalories (kcal)
Varies widely, typically 1000-2000+ kcal
TDEE
Total calories burned in a day, including activity.
Kilocalories (kcal)
Varies widely, typically 1500-3500+ kcal
Desired Weekly Weight Loss
Target rate for losing body mass.
Kilograms per week (kg/week)
0.25 – 1.0
Daily Calorie Deficit
Difference between TDEE and target intake for weight loss.
Kilocalories (kcal)
Varies, typically 250-1000 kcal
Target Daily Calorie Intake
Final calculated calorie goal for weight loss.
Kilocalories (kcal)
Varies widely
How to Use This Calories to Eat to Lose Weight Calculator
Using this calculator is straightforward and designed to provide you with actionable insights into your weight management journey. Follow these simple steps:
Input Your Details: Accurately enter your biological sex, age, current weight (in kg), and height (in cm).
Select Activity Level: Choose the activity factor that best represents your typical weekly exercise routine and daily movement. Be honest to get the most accurate TDEE estimate.
Set Your Goal: Decide on your desired weekly weight loss. For sustainable results and better health, aiming for 0.5 kg (1 lb) per week is generally recommended.
Calculate: Click the "Calculate" button.
How to Read the Results:
Basal Metabolic Rate (BMR): This is the number of calories your body burns at rest. It's the minimum energy needed to keep vital functions going.
Total Daily Energy Expenditure (TDEE): This is your BMR plus the calories burned through all daily activities, including exercise. It represents your maintenance calorie level.
Daily Calorie Deficit: This is the number of calories you need to consume less than your TDEE each day to achieve your set weight loss goal.
Target Daily Calorie Intake: This is your final calculated goal – the number of calories you should aim to eat each day to lose weight at your desired rate.
Decision-Making Guidance: Your target daily calorie intake is a guideline. Focus on consuming nutrient-dense foods to feel full and satisfied. If you find the target too difficult to maintain or if you experience excessive fatigue, consider adjusting your activity level or slightly increasing your calorie intake. Conversely, if weight loss stalls, ensure your inputs are accurate and consider a small further reduction in calories or an increase in activity. Remember, consistency is key for long-term success in weight management.
Key Factors That Affect Calories to Eat to Lose Weight Results
While the calculator provides a solid estimate, several factors can influence your actual calorie needs and weight loss progress:
Muscle Mass: Muscle tissue is more metabolically active than fat tissue, meaning individuals with higher muscle mass generally burn more calories at rest. Weight training can increase muscle mass over time, potentially increasing BMR.
Genetics: Individual genetic makeup plays a role in metabolic rate. Some people naturally have a faster metabolism than others, influencing how many calories they burn.
Hormonal Fluctuations: Hormones like thyroid hormones significantly impact metabolism. Conditions such as hypothyroidism can slow down metabolism, while hyperthyroidism can speed it up.
Body Composition: Beyond just weight and height, the ratio of lean body mass to fat mass is crucial. The calculator uses general formulas, but body composition analysis (like DEXA scans) offers a more precise picture.
Age and Sex: As mentioned in the formula, age and sex are factors. Metabolism tends to slow down with age, and men typically have a higher metabolic rate than women due to generally higher muscle mass.
Dietary Thermogenesis: The thermic effect of food (TEF) is the energy used to digest, absorb, and metabolize nutrients. Protein has a higher TEF than carbohydrates or fats, meaning your body burns slightly more calories digesting protein.
Sleep Quality: Poor sleep can disrupt hormones that regulate appetite (ghrelin and leptin), potentially leading to increased hunger and cravings, making adherence to a calorie deficit more challenging.
Medications: Certain medications can affect metabolism and appetite, influencing calorie expenditure and intake needs.
Frequently Asked Questions (FAQ)
How quickly can I expect to lose weight with this calculator's target?
If you consistently stick to your calculated target calorie intake, you can expect to lose approximately 0.5 kg (1 lb) per week for every 500 kcal daily deficit. Faster loss (e.g., 1 kg/week) requires a larger deficit (1000 kcal/day), which might be harder to sustain and could lead to nutrient deficiencies or muscle loss if not carefully managed.
Is the Mifflin-St Jeor equation the only way to calculate BMR?
No, other equations exist, such as the revised Harris-Benedict equation. However, Mifflin-St Jeor is currently considered one of the most accurate for estimating BMR in a general population. The results from different formulas can vary slightly.
What if my weight or activity level changes?
If your weight, activity level, or other factors change significantly, you should recalculate your calorie needs. As you lose weight, your TDEE will decrease, so you may need to adjust your intake further to continue losing weight.
Can I eat less than the calculated target for faster weight loss?
While technically possible, consuming significantly fewer calories than recommended (e.g., below 1200 kcal for women or 1500 kcal for men) is generally not advised without medical supervision. Very low-calorie diets can lead to muscle loss, nutrient deficiencies, fatigue, and a slowed metabolism, making long-term weight management more difficult.
Does the calculator account for exercise calories burned?
The calculator uses an "Activity Factor" that estimates the *average* calories burned from daily activities and planned exercise. For more precise tracking, you might use a fitness tracker to estimate calories burned during specific workouts and adjust your daily intake accordingly, but always err on the side of caution and avoid large fluctuations.
What kind of foods should I eat to meet my calorie goal?
Focus on whole, unprocessed foods like lean proteins, fruits, vegetables, whole grains, and healthy fats. These foods are nutrient-dense and more satiating, helping you feel fuller on fewer calories. Prioritize protein and fiber to support muscle mass and satiety.
How long should I follow this calorie target?
You should follow the target as long as you are actively trying to lose weight. Once you reach your goal weight, you'll need to recalculate your TDEE and slightly increase your calorie intake to a maintenance level to avoid regaining the lost weight.
Is it better to have a small deficit every day or a large deficit a few times a week?
For most people, a consistent, moderate deficit (around 500 kcal/day) leads to more sustainable and healthier weight loss than large, inconsistent deficits. Daily consistency helps regulate hunger hormones and prevents extreme cravings or fatigue.
Related Tools and Internal Resources
BMI CalculatorCalculate your Body Mass Index (BMI) to understand your weight category relative to your height.
Macronutrient CalculatorDetermine the ideal balance of protein, carbohydrates, and fats for your diet based on your goals.
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var tdeeData = [];
var targetData = [];
// Approximate daily calorie needs assuming weight loss continues
var dailyTarget = Math.max(1200, targetCalories); // Ensure target doesn't go below a safe minimum
var dailyTDEE = tdee;
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// This is a simplification. A more complex model would recalculate TDEE based on projected weight.
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