Mifflin St. Jeor Calculator

How to Calculate TDEE & BMR

Calculating your Total Daily Energy Expenditure (TDEE) and Basal Metabolic Rate (BMR) provides valuable insights into your daily calorie needs. The Mifflin St. Jeor equation is a widely used method for estimating these values based on factors such as age, gender, height, weight, and activity level. Here's a detailed explanation of how to calculate your TDEE and BMR using the Mifflin St. Jeor equation:

Mifflin St. Jeor Equation

The Mifflin St. Jeor equation consists of two parts:

1. Calculate Basal Metabolic Rate (BMR) using the Mifflin-St Jeor Equation:
   • For males: $$BMR = 10 * weight + 6.25 * height - 5 * age + 5$$
   • For females: $$BMR = 10 * weight + 6.25 * height - 5 * age - 161$$
   Where weight is in kg, height is in cm, and age is in years.
2. Calculate Total Daily Energy Expenditure (TDEE): $$TDEE = BMR * Activity Factor$$

The Activity Factor ranges from 1.2 for sedentary individuals to 1.9 for very active individuals.

Calculation Steps

1. Input personal data: age, gender, height, weight, and activity level.
2. Calculate BMR using the appropriate formula based on gender.
3. Multiply BMR by the activity factor to get TDEE, which represents your maintenance calories.

Example Calculation

Let's calculate the maintenance calories for a 30-year-old male who is 180 cm tall, weighs 75 kg, and has a moderately active lifestyle.

Step 1: Calculate BMR

$$\begin{align} BMR &= 10 * 75 + 6.25 * 180 - 5 * 30 + 5 \\ &= 750 + 1125 - 150 + 5 \\ &= 1730 \text{ calories/day} \end{align}$$

Step 2: Calculate TDEE (moderately active = 1.55)

$$\begin{align} TDEE &= 1730 * 1.55 \\ &= 2681.5 \text{ calories/day} \end{align}$$

Therefore, this person's estimated maintenance calories are 2682 calories per day.

Visual Representation

This doughnut chart illustrates the distribution of maintenance calories for our example calculation. The inner circle represents the Basal Metabolic Rate (BMR), which is the number of calories burned at rest. The outer ring shows the additional calories burned through daily activities and exercise. Together, they make up the Total Daily Energy Expenditure (TDEE), which represents the maintenance calories.