BMR & TDEE Daily Calorie Calculator
Determine your Basal Metabolic Rate and Total Daily Energy Expenditure based on the Mifflin-St Jeor Equation.
What is BMR and TDEE?
Understanding your body's energy requirements is the foundation of any successful fitness or weight management plan. Two of the most critical metrics are Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE).
BMR is the number of calories your body requires to function while at rest. Even if you were to stay in bed all day, your body still burns calories to keep your heart beating, lungs breathing, and organs functioning. This calculator uses the Mifflin-St Jeor Equation, which is currently considered the most accurate standard for predicting BMR.
TDEE is an estimation of how many calories you burn per day when exercise and daily movement are taken into account. It is calculated by multiplying your BMR by an activity factor. This number represents your "maintenance calories"—the amount you need to eat to stay exactly the same weight.
The Science Behind the Calculation
The formulas used in this tool are as follows:
- 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
Realistic Examples
To put this into perspective, let's look at two profiles:
- Example 1: A 30-year-old male weighing 85kg at 180cm height who is "Moderately Active." His BMR would be roughly 1,830 calories. When multiplied by the 1.55 activity factor, his TDEE becomes 2,836 calories. To lose weight, he should target around 2,336 calories.
- Example 2: A 25-year-old female weighing 60kg at 165cm height who is "Sedentary." Her BMR is approximately 1,365 calories. With a 1.2 activity factor, her TDEE is 1,638 calories. Her margin for calorie deficit is much smaller than the first example.
How to Use Your Results
If your goal is weight loss, you should aim to consume roughly 500 calories fewer than your TDEE each day. This typically results in a safe loss of about 0.5kg per week. If your goal is muscle gain, you should aim for a "surplus" of 200–500 calories above your TDEE while maintaining a consistent strength training routine.
Remember that these numbers are estimates. Metabolism can be influenced by muscle mass, hormonal health, and genetics. Use these results as a starting point and adjust based on your actual progress over 2-4 weeks.