Maintenance Calorie Calculator

What Are Maintenance Calories?

Maintenance calories represent the exact amount of energy your body requires each day to sustain your current body weight. This number accounts for your basal metabolic rate (BMR)—the energy needed for basic functions like breathing and circulation—plus the energy expended through physical activity and digestion. When your daily calorie intake matches this number, your weight remains stable. This calculator estimates your maintenance calories using the Mifflin-St Jeor equation, one of the most reliable formulas for predicting energy expenditure.

How Your Maintenance Calories Are Calculated

The calculation begins with your basal metabolic rate, which is determined by your sex, weight, height, and age. The Mifflin-St Jeor formula uses the following equations:

• For males: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
• For females: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161

Your BMR is then multiplied by an activity factor that corresponds to your typical daily movement level. These factors range from 1.2 (sedentary) to 1.9 (very active). The result is your total daily energy expenditure (TDEE), which is your maintenance calorie target.

How to Use This Calculator

Enter your current weight, height, age, and sex into the fields provided. Select the activity level that best describes your typical week. The calculator will return an estimate of the calories you need to consume daily to keep your weight unchanged. For the most accurate result, use your current weight rather than a goal weight, and be honest about your activity level.

Understanding Your Results

The number you receive is an estimate, not a precise measurement. Individual metabolism varies due to factors like muscle mass, genetics, hormone levels, and sleep quality. Your actual maintenance calories may differ by 100–300 calories per day from the calculated value. Use this number as a starting point and adjust based on your real-world weight trends over one to two weeks.

If you are highly active in a specific sport or have a physically demanding job, your actual needs may be higher than the standard activity multipliers suggest. Conversely, if you sit for most of the day outside of structured exercise, the "sedentary" or "lightly active" multiplier is likely more accurate.

Common Mistakes When Estimating Maintenance Calories

• Overestimating activity level: Many people select "moderately active" when they are actually sedentary or lightly active. This leads to an inflated calorie target and unintended weight gain.
• Using goal weight instead of current weight: The formula is designed for your current body mass. Using a future goal weight will produce an inaccurate estimate.
• Ignoring weight trends: A single day's reading on the scale is not reliable. Track your weight over several days and compare your average to your calorie intake to fine-tune the number.
• Not adjusting after weight change: As you lose or gain weight, your maintenance calories change. Recalculate every 5–10 pounds of weight change.

Practical Use Cases

Knowing your maintenance calories is useful for several common goals:

• Weight maintenance: If you are satisfied with your current weight, this number gives you a daily target to aim for.
• Weight loss: Subtract 300–500 calories from your maintenance number to create a sustainable calorie deficit for gradual fat loss.
• Weight gain: Add 300–500 calories to your maintenance number to support muscle growth or healthy weight gain.
• Diet planning: Use the estimate to structure your meals and snacks around a specific daily calorie budget.

Limitations of This Calculation

The Mifflin-St Jeor equation is validated for the general adult population but has limitations. It may be less accurate for:

• Individuals with very high muscle mass or very low body fat percentages
• People over age 60, as metabolic rate tends to decline with age
• Those with medical conditions affecting metabolism, such as thyroid disorders
• Pregnant or breastfeeding women, who have significantly different energy requirements

This calculator provides a general guideline. For personalized medical or nutritional advice, consult a registered dietitian or healthcare provider.