BMR Calculator helps you estimate your Basal Metabolic Rate the number of calories your body burns each day just to stay alive. With this free base calorie calculator, you can determine your daily energy needs, find your maintenance calories, or even plan a healthy calorie deficit to reach your fitness goals.
Whether you’re asking “what’s my BMR?” or trying to learn how to calculate a calorie deficit, this simple and accurate tool combines science-backed formulas with real-world usability. You’ll also get a quick estimate of your metabolic age, giving you a snapshot of how efficiently your body burns energy compared to your actual age.
Result
| Activity Level | Calories/day |
|---|
BMR Calculator
Estimate your Basal Metabolic Rate (BMR), how many calories you burn in a day (TDEE), maintenance calories, and a quick calorie deficit calculator. Includes Mifflin–St Jeor, Harris-Benedict, and Katch-McArdle (if body fat % is provided). Also shows a metabolic age (rough) based on your BMR.
Basal Metabolic Rate (BMR)
How many calories you burn in a day (TDEE)
Maintenance Calories
Calorie Deficit Targets
Metabolic Age (rough)
What’s my BMR and how do I use it?
Your BMR is the number of calories your body needs at rest. Multiply BMR by your activity factor to get your daily burn (TDEE) — this is your calorie maintenance calculator result. To create a plan, the base calorie calculator above shows maintenance and quick calorie deficit calculator targets. That’s exactly how to know how many calories you burn and how to calculate a calorie deficit.
The optional metabolic-age panel is a convenience feature akin to a simple metabolic age calculator and should not be used for medical decisions.
Educational use only. Formulas: Mifflin–St Jeor, Harris-Benedict (revised), Katch-McArdle.
Table of Contents
Discover How Many Calories You Burn in a Day
BMR Calculator helps you estimate your Basal Metabolic Rate — the number of calories your body burns each day just to stay alive. With this free base calorie calculator, you can determine your daily energy needs, find your maintenance calories, or even plan a healthy calorie deficit to reach your fitness goals.
Whether you’re asking “what’s my BMR?” or trying to learn how to calculate a calorie deficit, this simple and accurate tool combines science-backed formulas with real-world usability. You’ll also get a quick estimate of your metabolic age, giving you a snapshot of how efficiently your body burns energy compared to your actual age.
👉 Use the BMR Calculator above to find your daily calorie burn!
What Is BMR and Why Does It Matter?
Basal Metabolic Rate (BMR) is the amount of energy your body requires to perform basic functions — such as breathing, circulating blood, maintaining body temperature, and repairing cells — while at complete rest. In simpler terms, it’s the number of calories your body would burn if you stayed in bed all day doing nothing.
Knowing your BMR helps you understand your body’s baseline energy requirement. When you add physical activity, work, or exercise on top of that, you get your Total Daily Energy Expenditure (TDEE) — also known as your daily calorie burn. That’s the figure you need if you’re tracking your intake, planning weight loss, or optimizing muscle gain.
How to Use the BMR Calculator
Using this BMR Calculator is simple and takes less than a minute. Follow these steps:
- Choose your unit system — select Metric (kg, cm) or Imperial (lb, ft/in).
- Enter your details: age, sex, height, and weight.
- Pick an activity level to estimate how many calories you burn in a day.
- (Optional) Enter body fat percentage for advanced formulas like Katch-McArdle.
- Click “Calculate” to get your results instantly.
The calculator will display:
- Your BMR (Basal Metabolic Rate)
- Your TDEE (how many calories you burn daily)
- Your maintenance calories — ideal intake to stay at your current weight
- Calorie deficit recommendations for safe weight loss
- A rough metabolic age estimate
The Science Behind the BMR Calculator
This BMR Calculator uses three proven formulas used by scientists and nutritionists:
1. Mifflin–St Jeor Equation (most accurate)
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age – 161
2. Harris–Benedict Equation (classic version)
An older but still useful method that estimates daily energy needs using weight, height, and age.
3. Katch–McArdle Formula (for athletes)
BMR = 370 + (21.6 × Lean Body Mass in kg)
Use this version if you know your body fat percentage for better precision, especially if you are muscular or athletic.
How Many Calories Do You Burn in a Day?
If you’re wondering “how many calories do you burn in a day?” — your total calorie burn depends on your BMR and activity level. Here’s how to estimate your TDEE (Total Daily Energy Expenditure):
| Activity Level | Description | Multiplier |
|---|---|---|
| Sedentary | Little or no exercise | ×1.2 |
| Lightly Active | Light exercise 1–3 days/week | ×1.375 |
| Moderately Active | Moderate exercise 3–5 days/week | ×1.55 |
| Very Active | Intense exercise 6–7 days/week | ×1.725 |
| Extra Active | Heavy physical job + daily training | ×1.9 |
To calculate your daily calorie burn:
TDEE = BMR × Activity Level
How to Calculate a Calorie Deficit
If you want to lose fat, you need to consume fewer calories than your body burns. This is known as a calorie deficit.
- Small deficit (–250 kcal/day): Slow, sustainable fat loss.
- Moderate deficit (–500 kcal/day): Around 0.45 kg (1 lb) per week loss.
- Aggressive deficit (–750 kcal/day): Faster loss, but harder to maintain.
This calorie deficit calculator shows you exact numbers, making it easy to plan your meals and hit your goals without guesswork.
Calorie Maintenance Calculator
Once you’ve found your TDEE, you can determine your maintenance calories — the number of calories you need to eat to maintain your current weight. This is your base calorie calculator result.
If your goal is muscle gain, increase intake by about 10–15% above your maintenance level. For weight loss, aim for 10–20% below maintenance depending on your comfort and activity level.
What Is Metabolic Age?
Your metabolic age compares your Basal Metabolic Rate to the average BMR of people in different age groups. A metabolic age calculator estimates how efficiently your body burns energy compared to your peers.
If your metabolic age is lower than your actual age, it means your metabolism is strong. If it’s higher, lifestyle adjustments like more strength training, better sleep, and balanced nutrition can help improve your metabolism.
Why You Should Use a BMR Calculator
- Plan effective weight loss or muscle gain programs
- Understand your daily calorie burn
- Build custom meal plans based on energy needs
- Track changes in your metabolism over time
- Balance nutrition with physical activity for long-term health
Frequently Asked Questions (FAQ)
1. What’s my BMR and why should I know it?
Your BMR tells you how many calories your body needs just to function at rest. Knowing this helps you manage weight more efficiently and make data-based diet decisions.
2. How do I know how many calories I burn daily?
Multiply your BMR by your activity multiplier (between 1.2 and 1.9). This gives your TDEE — the total calories you burn daily through all activity and rest.
3. How do I calculate a calorie deficit?
Subtract 250–500 calories from your daily TDEE. That’s your target intake for steady fat loss.
4. What’s a healthy metabolic age?
Ideally, your metabolic age should be equal to or lower than your actual age. A lower metabolic age indicates higher metabolic efficiency.
5. What’s the difference between BMR and TDEE?
BMR is your resting energy burn. TDEE includes activity, workouts, and daily movement — making it a better measure for meal planning.
Conclusion
This all-in-one BMR Calculator is more than just a number-cruncher. It’s your personal calorie maintenance calculator, calorie deficit calculator, and metabolic age calculator in one easy tool.
Use it regularly to stay on top of your fitness goals, track progress, and understand how your body’s metabolism evolves over time. Remember, your BMR isn’t fixed as you gain or lose muscle, your energy needs change too. Stay consistent, and let data guide your journey toward better health.
BMR Calculator - Raw Calculator
BMR Calculator helps you estimate your Basal Metabolic Rate the number of calories your body burns each day just to stay alive. With this free base calorie calculator, you can determine your daily energy needs, find your maintenance calories, or even plan a healthy calorie deficit to reach your fitness goals.
Price Currency: USD
Operating System: All (Web, iOS, Android, Windows, macOS)
Application Category: Calculator