BMR & Daily Calorie Calculator
Estimate your body's baseline calorie needs and total daily energy expenditure using the Mifflin-St Jeor formula.
Enter Your Details
How It Works
- Select your preferred unit system and enter your personal details.
- Choose the activity level that best matches your weekly routine.
- Your Basal Metabolic Rate (BMR) is calculated instantly.
- The table on the right shows your Total Daily Energy Expenditure (TDEE), with your selected level highlighted for easy reference.
Your Calorie Needs
The calories your body needs to function at complete rest.
Daily Calorie Needs (TDEE)
Our Key Features
- Accurate Mifflin-St Jeor Formula We use the modern Mifflin-St Jeor equation, widely considered the gold standard by nutrition experts for accurately predicting your Basal Metabolic Rate (BMR).
- Complete TDEE Breakdown Don't just get your BMR. See a full, actionable breakdown of your Total Daily Energy Expenditure (TDEE) across five different activity levels, from sedentary to extra active.
- Smart Unit Conversion Easily switch between Metric (kg/cm) and Imperial (lbs/ft/in). The tool intelligently converts your existing numbers so you never have to re-enter them.
- Instant, Free & Private Get your comprehensive results instantly with no paywalls or sign-ups. All calculations are performed in your browser, ensuring your personal data is never saved or sent to us.
Understanding Your Results
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic, life-sustaining functions at rest, like breathing, circulation, and cell production. TDEE (Total Daily Energy Expenditure) is the total number of calories you burn in a day. It's your BMR plus the calories you burn from physical activity and digesting food. TDEE is a more practical number for managing your weight.
Which formula does this calculator use?
This calculator uses the **Mifflin-St Jeor equation**, which was developed in the 1990s. It is widely regarded by nutrition experts as more accurate than the older Harris-Benedict equation because it better reflects the lifestyles of the modern population. The formula is:
• Men: 10 * weight (kg) + 6.25 * height (cm) - 5 * age (y) + 5
• Women: 10 * weight (kg) + 6.25 * height (cm) - 5 * age (y) - 161
How can I use these numbers for weight management?
To **maintain** your current weight, you should aim to consume roughly your TDEE in calories per day. To **lose weight**, you should consume fewer calories than your TDEE (a common deficit is 500 calories/day for about 1 lb/0.5 kg loss per week). To **gain weight**, you should consume more calories than your TDEE. Always consult with a healthcare professional before making significant dietary changes.
Why is biological sex required for this calculation?
The standard metabolic formulas, including Mifflin-St Jeor, were developed using biological sex as a variable because of physiological differences in body composition (e.g., muscle mass vs. fat mass) that affect metabolic rate. The "Male" and "Female" options refer to the sex assigned at birth, as this is what the formula is based on. We recognize this is a limitation of the model and does not encompass the full spectrum of gender identity.
Your Body's Energy Blueprint: A Guide to BMR and TDEE
The question "how many calories should I eat?" is central to any health or fitness journey, but the answer is deeply personal. A one-size-fits-all approach rarely works. Our BMR and Calorie Calculator is designed to give you a personalized, science-backed starting point by decoding your body's unique energy needs.
BMR: Your Body's Baseline Operating Cost
Think of your Basal Metabolic Rate (BMR) as the energy your body needs just to stay "on," like a car idling in neutral. It's the minimum number of calories required to perform essential functions like breathing, circulating blood, and regulating body temperature if you were to rest for 24 hours. This number is your metabolic foundation, influenced by your age, sex, weight, and height. Our calculator uses the highly regarded Mifflin-St Jeor equation to give you an accurate estimate of this baseline.
TDEE: The "Real World" Calorie Number
While BMR is fascinating, it's not the number you should use for your daily planning. That's where Total Daily Energy Expenditure (TDEE) comes in. TDEE takes your BMR and adds the calories you burn through all other activities: walking, working, exercising, and even digesting food. This is the "real world" number that represents your total daily calorie burn.
Putting Your Results Into Action
The TDEE table is your actionable guide for weight management:
- For Weight Maintenance: Your goal is to match your calorie intake with your TDEE for your current activity level. This creates an energy balance where you are consuming as many calories as you are burning.
- For Weight Loss: To lose weight, you need to create a calorie deficit. This means consistently consuming fewer calories than your TDEE. A common and sustainable deficit is around 500 calories per day, which typically leads to about 1 lb (0.5 kg) of weight loss per week.
- For Weight Gain: To gain weight, typically in the form of muscle mass, you need a calorie surplus. This means consuming more calories than your TDEE to provide your body with the extra energy needed for tissue growth, combined with appropriate strength training.
By understanding both your BMR and TDEE, you move from guesswork to an informed strategy. This calculator provides the blueprint, empowering you to make tailored decisions that align with your unique body and wellness goals.