Biological sex affects Basal Metabolic Rate (BMR).
Please enter a valid age (15-100).
Metabolic rate typically decreases with age.
Current body weight.
Current height.
Current body weight in pounds.
Height in feet and inches.
Sedentary (Office job, little exercise)
Lightly Active (Exercise 1-3 days/week)
Moderately Active (Exercise 3-5 days/week)
Very Active (Exercise 6-7 days/week)
Super Active (Physical job + training)
Select the option that best describes your weekly routine.
Daily Calories to Maintain Weight
0
This is your Total Daily Energy Expenditure (TDEE).
Basal Metabolic Rate (BMR)
0
Calories at complete rest
Weekly Maintenance
0
Total weekly calories
Daily Deficit (-500)
0
For ~0.5kg weight loss/week
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Energy Expenditure Breakdown
Fig 1. Comparison of BMR vs. Maintenance vs. Weight Management Goals.
Macronutrient Breakdown (Maintenance)
Diet Type
Protein (g)
Fats (g)
Carbs (g)
Table 1: Suggested daily macronutrient intake based on maintenance calories.
What is a Calories Required to Maintain Weight Calculator?
A calories required to maintain weight calculator is a digital tool designed to estimate your Total Daily Energy Expenditure (TDEE). In nutritional science and physiology, maintenance calories represent the precise number of energy units (calories) your body consumes daily to perform basic biological functions and support physical activity without gaining or losing body mass.
This calculator is essential for anyone looking to stabilize their physique, athletes in a maintenance phase, or individuals transitioning out of a diet. Unlike generic calculators, a dedicated tool for maintenance considers specific biological variables such as age, gender, height, and activity thermogenesis.
Common Misconception: Many people believe that eating 2,000 calories is a universal standard. In reality, a petite sedentary woman may only need 1,400 calories to maintain weight, while a tall, active man may require over 3,000. Using a calories required to maintain weight calculator ensures your nutritional intake is aligned with your unique metabolic output.
The Formula: How We Calculate Maintenance Calories
To determine the calories required to maintain weight, we utilize a two-step mathematical process. First, we calculate the Basal Metabolic Rate (BMR), and then we apply an Activity Factor.
Step 1: The Mifflin-St Jeor Equation
This calculator uses the Mifflin-St Jeor equation, widely regarded by the Academy of Nutrition and Dietetics as the most accurate standard for estimating BMR.
Men: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
Women: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Step 2: Total Daily Energy Expenditure (TDEE)
Once BMR is established, we multiply it by a factor representing your activity level to find your maintenance calories:
Maintenance Calories = BMR × Activity Multiplier
Variable
Meaning
Typical Range/Unit
BMR
Energy burned at complete rest
1,200 – 2,200 kcal/day
Activity Multiplier
Factor for movement and exercise
1.2 (Sedentary) to 1.9 (Athlete)
NEAT
Non-Exercise Activity Thermogenesis
15% – 30% of TDEE
TEF
Thermic Effect of Food
~10% of Total Intake
Table 2: Key variables in the maintenance calorie formula.
Practical Examples of Maintenance Calculations
Example 1: The Sedentary Office Worker
Profile: Sarah is a 35-year-old female, 165 cm tall, weighing 60 kg. She works a desk job and does not exercise regularly.
Inputs: Female, 35 years, 165 cm, 60 kg, Sedentary (1.2).
Interpretation: Mark requires a significantly higher intake just to maintain his mass due to high activity thermogenesis. A 2,000 calorie diet would cause rapid weight loss for him.
How to Use This Calculator
Select Gender: This adjusts the base constant in the BMR equation.
Enter Age: Metabolism slows slightly with age; accuracy requires the correct year.
Input Physical Stats: Enter accurate height and weight. Use the unit toggle if you prefer Imperial (lbs/ft) over Metric (kg/cm).
Choose Activity Level: Be honest. "Moderately Active" implies structured exercise 3-5 times a week, not just walking the dog.
Analyze Results: The primary number is your maintenance target. The table below it offers macronutrient suggestions (Protein/Fats/Carbs) to hit that target healthily.
Use the Copy Results button to save your data for your nutritionist or personal records.
Key Factors That Affect Your Maintenance Calories
While the calories required to maintain weight calculator provides a highly accurate estimate, several biological and environmental factors influence the exact number:
1. Muscle Mass (Lean Body Mass)
Muscle tissue is metabolically expensive. A person with 80kg of lean muscle burns significantly more calories at rest than a person of the same weight with higher body fat. This calculator assumes average body composition.
2. Age and Hormonal Profile
As we age, sarcopenia (natural muscle loss) and hormonal changes (lower testosterone or estrogen) reduce BMR. This typically requires reducing intake by roughly 10 calories per day for each year past age 20 to maintain weight accurately.
3. Non-Exercise Activity Thermogenesis (NEAT)
NEAT includes fidgeting, standing, and walking. It can vary by up to 2,000 calories between individuals. If you have a high NEAT, your actual maintenance might be higher than calculated.
4. Thermic Effect of Food (TEF)
Protein requires more energy to digest (20-30% of calories burned) compared to fats or carbs (0-15%). A high-protein diet effectively raises your maintenance threshold slightly.
5. Genetics and Epigenetics
Genetic "thrifty genes" can make some metabolisms more efficient (burning less energy), while others are wasteful (burning more). This variance explains why some people can eat more without gaining weight.
6. History of Dieting
Chronic dieting can lead to "metabolic adaptation," where the body learns to function on fewer calories. If you have dieted recently, your maintenance level might be temporarily lower than the formula predicts.
Frequently Asked Questions (FAQ)
1. How often should I recalculate my maintenance calories?
You should recalculate every time your body weight changes by more than 5-10 lbs (2-5 kg), or if your daily activity level changes significantly (e.g., switching from a desk job to retail).
2. Is this calculator 100% accurate?
No calculator is perfect. This tool provides an estimate within +/- 5-10%. We recommend using the result as a starting point and adjusting based on scale weight trends over 2 weeks.
3. Can I maintain weight while building muscle?
Yes, this is called "body recomposition." It is most effective when eating exactly at your calculated maintenance calories while engaging in resistance training and consuming high protein.
4. Why is my maintenance calorie number so high?
If you selected a high activity level, the multiplier drastically increases the result. Ensure you aren't overestimating your exercise frequency or intensity.
5. Does sleep affect maintenance calories?
Indirectly, yes. Poor sleep raises cortisol and lowers insulin sensitivity, which can lower your metabolic rate and increase fat storage signaling.
6. What if I eat below maintenance?
If you consistently eat below the number provided by the calories required to maintain weight calculator, you will enter a caloric deficit and lose weight.
7. Should I count exercise calories separately?
Generally, no. The "Activity Level" input already accounts for your exercise. Adding exercise calories on top of this result usually leads to overeating.
8. How do I track if I am maintaining?
Weigh yourself daily for two weeks and take the average. If the average remains stable, you are at maintenance. If it rises, reduce intake by 100-200 calories.
Related Tools and Internal Resources
Explore more tools to optimize your health and nutritional planning:
Disclaimer: The results provided by this calories required to maintain weight calculator are estimates based on standard metabolic formulas. This information is for educational purposes only and does not constitute medical advice. Consult a healthcare professional before making significant changes to your diet or exercise routine.
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