body {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #f8f9fa;
color: #333;
line-height: 1.6;
margin: 0;
padding: 20px;
}
.calculator-container {
max-width: 700px;
margin: 30px auto;
background-color: #ffffff;
padding: 30px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}
h1, h2 {
color: #004a99;
text-align: center;
margin-bottom: 20px;
}
.input-group {
margin-bottom: 20px;
display: flex;
align-items: center;
flex-wrap: wrap;
}
.input-group label {
display: inline-block;
width: 150px;
margin-right: 15px;
font-weight: 600;
color: #004a99;
flex-shrink: 0;
}
.input-group input[type="number"],
.input-group select {
flex-grow: 1;
padding: 10px 12px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 1rem;
min-width: 180px;
box-sizing: border-box;
}
.input-group input[type="number"]:focus,
.input-group select:focus {
border-color: #004a99;
outline: none;
box-shadow: 0 0 0 0.2rem rgba(0, 74, 153, 0.25);
}
button {
display: block;
width: 100%;
padding: 12px 20px;
background-color: #004a99;
color: white;
border: none;
border-radius: 4px;
font-size: 1.1rem;
font-weight: 600;
cursor: pointer;
transition: background-color 0.3s ease;
margin-top: 10px;
}
button:hover {
background-color: #003f80;
}
.result-container {
margin-top: 30px;
padding: 20px;
background-color: #e7f3ff;
border-left: 5px solid #28a745;
border-radius: 4px;
text-align: center;
}
.result-container h3 {
margin-top: 0;
color: #004a99;
}
.result-value {
font-size: 2.5rem;
font-weight: bold;
color: #28a745;
margin-top: 10px;
}
.article-section {
margin-top: 40px;
padding-top: 20px;
border-top: 1px solid #eee;
}
.article-section h2 {
text-align: left;
margin-bottom: 15px;
}
.article-section p, .article-section ul {
margin-bottom: 15px;
}
.article-section strong {
color: #004a99;
}
@media (max-width: 600px) {
.input-group {
flex-direction: column;
align-items: flex-start;
}
.input-group label {
width: auto;
margin-bottom: 8px;
}
.input-group input[type="number"],
.input-group select {
width: calc(100% – 24px);
}
.calculator-container {
padding: 20px;
}
}
Understanding Your Protein and Calorie Needs
Estimating your daily caloric and macronutrient needs is a fundamental step towards achieving health, fitness, and weight management goals. This calculator provides personalized estimates based on your weight, height, age, gender, and activity level.
Basal Metabolic Rate (BMR)
The calculation begins with determining your Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest to maintain basic functions like breathing, circulation, and cell production. We use the Mifflin-St Jeor equation, which is widely considered one of the most accurate formulas:
- 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
Total Daily Energy Expenditure (TDEE)
Once your BMR is calculated, it's adjusted for your physical activity level to estimate your Total Daily Energy Expenditure (TDEE). TDEE represents the total number of calories you burn in a day, including all daily activities. This is achieved by multiplying your BMR by an activity factor:
- Sedentary: BMR × 1.2
- Lightly active: BMR × 1.375
- Moderately active: BMR × 1.55
- Very active: BMR × 1.725
- Extra active: BMR × 1.9
The TDEE is your estimated daily calorie intake requirement to maintain your current weight.
Macronutrient Distribution
After estimating your daily calorie needs, the calculator then suggests a macronutrient breakdown (protein, carbohydrates, and fat). A common, balanced approach for general health and fitness is as follows:
- Protein: Typically recommended at 1.2 to 2.2 grams per kilogram of body weight. For this calculator, we use a common target of 1.6 g/kg for general fitness.
- Fat: Often set around 20-30% of total daily calories. We'll use 25%.
- Carbohydrates: The remaining calories are filled by carbohydrates.
The caloric values for macronutrients are:
- 1 gram of Protein = 4 calories
- 1 gram of Carbohydrates = 4 calories
- 1 gram of Fat = 9 calories
How to Use the Calculator
- Enter your current Weight in kilograms.
- Enter your Height in centimeters.
- Enter your Age in years.
- Select your Gender.
- Choose your typical Activity Level from the dropdown.
- Click "Calculate Daily Needs".
The results will show your estimated daily calorie intake to maintain your weight, along with recommended grams of protein, carbohydrates, and fat based on general guidelines. Remember, these are estimates. Individual needs can vary based on metabolism, specific health conditions, and precise fitness goals (e.g., muscle gain vs. fat loss). Consulting a healthcare professional or a registered dietitian is always recommended for personalized advice.
function calculateMacros() {
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var age = parseFloat(document.getElementById("age").value);
var gender = document.getElementById("gender").value;
var activityLevel = parseFloat(document.getElementById("activityLevel").value);
var bmr = 0;
// Validate inputs
if (isNaN(weight) || weight <= 0 ||
isNaN(height) || height <= 0 ||
isNaN(age) || age tdee) proteinCalories = tdee;
if (fatCalories > tdee) fatCalories = tdee;
if (carbCalories < 0) carbCalories = 0;
if (proteinGrams < 0) proteinGrams = 0;
if (fatGrams < 0) fatGrams = 0;
if (carbGrams < 0) carbGrams = 0;
// Adjust proportions if necessary after initial calculation
var remainingCaloriesAfterProtein = tdee – proteinCalories;
if (remainingCaloriesAfterProtein < 0) remainingCaloriesAfterProtein = 0;
var adjustedFatCalories = remainingCaloriesAfterProtein * 0.25;
var adjustedFatGrams = adjustedFatCalories / 9;
var adjustedCarbCalories = remainingCaloriesAfterProtein – adjustedFatCalories;
var adjustedCarbGrams = adjustedCarbCalories / 4;
// Handle potential rounding issues or negative carbs if protein is very high
if (adjustedCarbGrams < 0) adjustedCarbGrams = 0;
if (adjustedFatGrams < 0) adjustedFatGrams = 0;
// Display results
document.getElementById("dailyCalories").textContent = tdee.toFixed(0);
document.getElementById("dailyProtein").textContent = proteinGrams.toFixed(0);
document.getElementById("dailyCarbs").textContent = adjustedCarbGrams.toFixed(0);
document.getElementById("dailyFat").textContent = adjustedFatGrams.toFixed(0);
}