Male
Female
Select your gender for more accurate BMR calculation.
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/physical job)
Choose the option that best describes your daily physical activity.
Enter your target weight in kilograms.
Enter your desired weekly weight loss (e.g., 0.5 kg).
Calculated using the Mifflin-St Jeor equation for BMR and standard TDEE principles.
Weight Loss Progress Projection
Key Input Variables
Variable
Meaning
Unit
Typical Range
Current Weight
Starting body weight.
kg
40 – 200+
Height
Individual's height.
cm
140 – 200+
Age
Individual's age in years.
Years
18 – 80+
Activity Level Multiplier
Represents daily energy expenditure from activity.
Unitless
1.2 – 1.9
Goal Weight
Target body weight.
kg
30 – 150+
Weekly Goal
Desired rate of weight loss per week.
kg/week
0.1 – 2.0
What is CICO (Calories In Calories Out)?
CICO, standing for "Calories In Calories Out," is a fundamental principle of weight management. It's the most straightforward way to understand how your body gains, loses, or maintains weight. The concept is based on the laws of thermodynamics: if you consume more calories than your body burns, you gain weight (an energy surplus). If you consume fewer calories than your body burns, you lose weight (an energy deficit). If your calorie intake equals your calorie expenditure, your weight remains stable.
The "Calories In" refers to all the energy you consume through food and beverages. The "Calories Out" refers to the total energy your body expends daily, which includes your Basal Metabolic Rate (BMR) – the calories burned at rest to maintain vital functions – plus the calories burned through physical activity, digestion (thermic effect of food), and non-exercise activity thermogenesis (NEAT).
Who Should Use the CICO Calculator?
Anyone looking to manage their weight can benefit from understanding their CICO. This includes individuals aiming for:
Weight Loss: Creating a sustainable calorie deficit.
Weight Gain: Creating a calorie surplus, often for muscle building.
Weight Maintenance: Aligning calorie intake with expenditure.
It's particularly useful for those who find tracking macronutrients too complex or who want a clear, science-based approach to their diet.
Common Misconceptions About CICO
Despite its simplicity, CICO is sometimes misunderstood. A common misconception is that "all calories are equal," meaning a calorie from a salad is the same as a calorie from a candy bar in terms of weight change. While technically true for pure energy balance, it ignores nutrient density, satiety, and overall health impacts. Another misconception is that CICO is the *only* factor; hormonal imbalances, sleep, stress, and metabolism can influence energy expenditure and absorption, though CICO remains the overarching principle.
CICO Calculator Formula and Mathematical Explanation
Our CICO calculator to lose weight utilizes well-established formulas to estimate your daily caloric needs and project your weight loss trajectory.
Step 1: Basal Metabolic Rate (BMR) Calculation
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
BMR represents the calories your body burns at complete rest to sustain basic life functions like breathing, circulation, and cell production.
Step 2: Total Daily Energy Expenditure (TDEE) Calculation
TDEE is your BMR multiplied by an activity factor. This accounts for the calories burned through all activities, from your workout to typing at your desk.
TDEE = BMR * Activity Level Multiplier
The activity level multipliers are standard estimates:
Sedentary: 1.2
Lightly Active: 1.375
Moderately Active: 1.55
Very Active: 1.725
Extra Active: 1.9
Step 3: Target Daily Calorie Intake for Weight Loss
To lose weight, you need to consume fewer calories than your TDEE, creating a calorie deficit. A common and generally safe deficit is around 500-1000 calories per day, aiming for a loss of approximately 0.5-1 kg per week (since 1 kg of fat is roughly equivalent to 7700 calories).
The calculator determines the required deficit based on your weekly goal:
We ensure the target calories don't fall below a safe minimum, typically around 1200 kcal for women and 1500 kcal for men, though this can vary.
Variables Table
Variable
Meaning
Unit
Typical Range
Current Weight
Your starting body weight.
kg
40 – 200+
Height
Your physical height.
cm
140 – 200+
Age
Your age in years.
Years
18 – 80+
Gender
Biological sex, influencing BMR calculation.
N/A
Male / Female
Activity Level Multiplier
Factor representing daily energy expenditure from physical activity.
Unitless
1.2 (Sedentary) – 1.9 (Extra Active)
BMR
Basal Metabolic Rate: Calories burned at rest.
kcal/day
800 – 2000+
TDEE
Total Daily Energy Expenditure: Total calories burned daily.
kcal/day
1500 – 4000+
Goal Weight
Your target body weight.
kg
30 – 150+
Weekly Goal
Desired rate of weight loss.
kg/week
0.1 – 2.0
Required Daily Deficit
Calorie reduction needed daily to meet weekly goal.
kcal/day
200 – 1400+
Target Daily Calories
Recommended daily calorie intake for weight loss.
kcal/day
1200 – 2500+
Practical Examples (Real-World Use Cases)
Example 1: Sustainable Weight Loss
Scenario: Sarah is a 30-year-old female, 170 cm tall, currently weighing 75 kg. She works a desk job (lightly active) and wants to reach a goal weight of 68 kg. She aims for a sustainable weight loss of 0.5 kg per week.
Inputs:
Current Weight: 75 kg
Height: 170 cm
Age: 30 years
Gender: Female
Activity Level: Lightly active (1.375)
Goal Weight: 68 kg
Weekly Goal: 0.5 kg
Calculated Results:
BMR: Approximately 1444 kcal/day
TDEE: Approximately 1981 kcal/day
Required Daily Deficit: Approximately 700 kcal/day
Target Daily Calories: Approximately 1281 kcal/day
Estimated Time to Reach Goal: Approximately 10 weeks (based on 7kg loss at 0.5kg/week)
Interpretation: To lose 0.5 kg per week and reach her goal weight of 68 kg, Sarah should aim to consume around 1281 calories per day. This deficit is significant enough for weight loss but likely manageable and sustainable for her activity level and goals.
Example 2: Faster Weight Loss Goal
Scenario: Mark is a 45-year-old male, 180 cm tall, weighing 90 kg. He is moderately active (exercises 4 times a week) and wants to lose 5 kg in 6 weeks for an upcoming event.
Inputs:
Current Weight: 90 kg
Height: 180 cm
Age: 45 years
Gender: Male
Activity Level: Moderately active (1.55)
Goal Weight: 85 kg
Weekly Goal: ~0.83 kg (5kg / 6 weeks)
Calculated Results:
BMR: Approximately 1768 kcal/day
TDEE: Approximately 2741 kcal/day
Required Daily Deficit: Approximately 980 kcal/day
Target Daily Calories: Approximately 1761 kcal/day
Estimated Time to Reach Goal: 6 weeks (as planned)
Interpretation: Mark needs to create a substantial daily deficit of nearly 980 calories. His target intake is around 1761 kcal. This is achievable but requires consistent adherence to his diet and exercise plan. He needs to be mindful of not dropping calories too low, as 1761 kcal is still a reasonable intake for his activity level, but pushing for more than 1kg/week loss might be too aggressive long-term.
How to Use This CICO Calculator
Using the CICO calculator to lose weight is designed to be simple and intuitive. Follow these steps to get your personalized calorie targets:
Enter Current Weight: Input your current body weight in kilograms.
Enter Height: Provide your height in centimeters.
Enter Age: Input your age in years.
Select Gender: Choose 'Male' or 'Female' for the most accurate BMR calculation.
Choose Activity Level: Select the option that best reflects your daily physical activity from the dropdown menu. Be honest for the most accurate results.
Enter Goal Weight: Input the target weight you wish to achieve in kilograms.
Set Weekly Goal: Specify how many kilograms you aim to lose each week. A range of 0.5 kg to 1 kg is generally considered safe and sustainable.
Click Calculate: Press the 'Calculate' button to see your results.
How to Read Your Results
Main Result (Target Daily Calories): This is the primary number you should focus on. It represents the estimated daily calorie intake required to achieve your specified weekly weight loss goal.
BMR: Your Basal Metabolic Rate shows how many calories your body burns at rest.
TDEE: Your Total Daily Energy Expenditure indicates your total daily calorie burn, including activity.
Weight Loss Projection Chart: Visualize your potential weight loss journey over time based on your target daily calories.
Variables Table: Provides a breakdown of the input variables and their significance.
Decision-Making Guidance
Your calculated target daily calories provide a roadmap. To succeed, you need to ensure your actual food intake aligns with this target. This often involves:
Tracking Your Intake: Use a food diary or app to log everything you eat and drink.
Choosing Nutrient-Dense Foods: Focus on whole foods that provide volume and satiety with fewer calories (vegetables, lean proteins, fruits).
Adjusting as Needed: If you're not losing weight as expected, re-evaluate your intake tracking accuracy or consider a slightly lower calorie target (within safe limits). If you feel overly fatigued or deprived, your target might be too aggressive.
Consulting Professionals: For personalized advice, especially with underlying health conditions, consult a registered dietitian or healthcare provider. Remember, this calculator provides an estimate.
Key Factors That Affect CICO Results
While the CICO principle is straightforward, several factors can influence the accuracy of calculator estimates and your actual weight management journey. Understanding these can help you interpret your results and make necessary adjustments.
Metabolic Adaptation: As you lose weight, your BMR and TDEE naturally decrease because you have less body mass to maintain. This means your calorie needs will eventually lower, and you may need to adjust your intake or activity further to continue losing weight. Your body can also become more "efficient" at burning fewer calories.
Hormonal Influences: Hormones like thyroid hormones, cortisol (stress), leptin (satiety), and ghrelin (hunger) play a significant role in regulating metabolism and appetite. Conditions like hypothyroidism can significantly lower BMR, making weight loss more challenging. Stress can also lead to increased cortisol levels, which may promote fat storage.
Body Composition: Muscle tissue burns more calories at rest than fat tissue. Two individuals with the same weight, height, and age but different body compositions (e.g., one more muscular) will have different BMRs. Our calculator uses general formulas, but a highly muscular individual might have a higher TDEE than predicted.
Digestion Efficiency (Thermic Effect of Food – TEF): While included in TDEE calculations, the exact TEF varies. Protein has a higher TEF than carbohydrates or fats, meaning your body burns more calories digesting protein. This is one reason why high-protein diets can aid weight loss.
Sleep Quality and Quantity: Poor sleep disrupts hormones that regulate appetite (increasing ghrelin, decreasing leptin) and can negatively impact metabolism. Chronic sleep deprivation can make adhering to a calorie deficit much harder and potentially hinder fat loss.
Medications and Health Conditions: Certain medications (e.g., some antidepressants, corticosteroids) can cause weight gain or affect metabolism. Chronic health conditions can also influence energy needs and expenditure. Always consult a doctor if you suspect these are impacting your weight.
NEAT (Non-Exercise Activity Thermogenesis): This includes all the calories burned from activities outside of formal exercise – fidgeting, walking around the office, standing, etc. NEAT can vary significantly between individuals and can be a substantial component of daily calorie expenditure, often underestimated.
Frequently Asked Questions (FAQ)
Q1: Is CICO the only factor in weight loss?
While CICO is the primary driver of weight change based on energy balance, other factors like hormonal health, sleep, stress, genetics, and nutrient absorption play supporting roles. However, consistently maintaining a calorie deficit will lead to weight loss regardless of these other influences, though they can affect the rate and ease of the process.
Q2: How accurate is the Mifflin-St Jeor equation?
The Mifflin-St Jeor equation is considered one of the most accurate BMR estimation formulas currently available for the general population. However, it is still an estimate. Individual metabolic rates can vary.
Q3: What if my TDEE is lower than the calculator suggests?
Your TDEE might be lower if your activity level is overestimated, or if you've experienced metabolic adaptation from previous dieting. If you're consistently not losing weight despite adhering to your target calories, it's advisable to reassess your activity level, ensure accurate tracking, and consider a slight reduction in calorie intake or an increase in physical activity. Consulting a professional is recommended.
Q4: Can I eat back calories burned from exercise?
You can, but it requires careful tracking. Exercise increases your TDEE, meaning you have more "calories out." If you consume the same number of calories as before exercising, you create a larger deficit. If you "eat back" the exercise calories, you are essentially maintaining your original TDEE target. Many people find it easier to set a target based on their TDEE without exercise and then view exercise as a way to accelerate deficit creation or enjoy more food within their budget.
Q5: What is NEAT and how can I increase it?
NEAT stands for Non-Exercise Activity Thermogenesis. It includes all calories burned from movements that aren't formal exercise, like fidgeting, standing, walking around, household chores, and even playing with children. You can increase NEAT by choosing to stand more, taking the stairs, parking further away, going for short walks throughout the day, and generally being more active in your daily routines.
Q6: Is it safe to aim for more than 1 kg of weight loss per week?
While possible, losing more than 1 kg (approx. 2.2 lbs) per week is often unsustainable and can lead to muscle loss, nutrient deficiencies, fatigue, and gallstones. Rapid weight loss is generally not recommended for long-term health and maintenance. A slower, steady rate of 0.5-1 kg per week is usually preferred.
Q7: How long does it take for CICO changes to show results?
If you accurately create a consistent calorie deficit, you should start seeing results within 1-2 weeks. However, daily weight fluctuations are normal due to water retention, food volume, and other factors. Consistent loss over weeks and months is the best indicator of success.
Q8: What should I do if my weight loss stalls?
Weight loss plateaus are common. Re-evaluate your calorie intake accuracy (are you tracking everything?), your activity level (has it decreased?), and consider if metabolic adaptation has occurred. You might need to slightly decrease your calorie target, increase your exercise duration or intensity, or focus on increasing NEAT. Patience and consistency are key.