Basal Metabolic Rate Bmr Calculator

Your Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic, life-sustaining functions at rest. This includes breathing, circulation, cell production, and nutrient processing. Understanding your BMR is a crucial first step in managing your weight and optimizing your overall health and fitness. It represents the absolute minimum calories you'd burn if you were to lie in bed all day without moving. Your total daily energy expenditure (TDEE) is your BMR plus the calories you burn through physical activity and the thermic effect of food.

Several factors influence your BMR, including your age, sex, weight, and height. Genetics also plays a role. Generally, men have a higher BMR than women due to typically having more muscle mass. Muscle tissue burns more calories at rest than fat tissue. As we age, our BMR tends to decrease, partly because muscle mass often declines.

This calculator uses the Mifflin-St Jeor equation, which is considered one of the most accurate formulas for estimating BMR. It is:

• 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

Once you have your BMR, you can use it to estimate your Total Daily Energy Expenditure (TDEE) by multiplying your BMR by an activity factor:

• Sedentary (little to no exercise): BMR × 1.2
• Lightly active (exercise 1-3 days/week): BMR × 1.375
• Moderately active (exercise 3-5 days/week): BMR × 1.55
• Very active (exercise 6-7 days/week): BMR × 1.725
• Extra active (very intense exercise & physical job): BMR × 1.9

Using this information, you can better tailor your diet and exercise plan to meet your specific health goals, whether it's weight loss, weight gain, or maintenance.

Male Female

function calculateBMR() { var gender = document.getElementById("gender").value; var weight = parseFloat(document.getElementById("weight").value); var height = parseFloat(document.getElementById("height").value); var age = parseInt(document.getElementById("age").value); var bmr = 0; if (isNaN(weight) || isNaN(height) || isNaN(age) || weight <= 0 || height <= 0 || age <= 0) { document.getElementById("result").innerHTML = "Please enter valid positive numbers for all fields."; return; } if (gender === "male") { bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5; } else { // female bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161; } document.getElementById("result").innerHTML = "Your estimated Basal Metabolic Rate (BMR) is: " + bmr.toFixed(2) + " calories per day."; }