Estimate your daily calorie needs during pregnancy.
Sedentary (little or no exercise)
Lightly Active (light exercise/sports 1-3 days/week)
Moderately Active (moderate exercise/sports 3-5 days/week)
Very Active (hard exercise/sports 6-7 days a week)
Extra Active (very hard exercise/sports & physical job)
First Trimester (Weeks 1-12)
Second Trimester (Weeks 13-28)
Third Trimester (Weeks 29-40)
Estimated Daily Calorie Needs:
— kcal
Understanding Your Pregnancy Calorie Needs
Pregnancy is a remarkable period of growth and development, not just for the baby but also for the mother. Adequate nutrition is paramount, and this includes ensuring sufficient calorie intake to support both maternal health and fetal development. However, the exact calorie needs are not static and vary significantly based on several factors.
The Science Behind the Calculation
This calculator uses a modified version of the Mifflin-St Jeor equation, a widely accepted formula for estimating Basal Metabolic Rate (BMR), and then adjusts it for pregnancy and activity level.
1. Basal Metabolic Rate (BMR) Calculation:
The Mifflin-St Jeor equation estimates the calories your body burns at rest. For women, it is:
BMR = (10 * weight in kg) + (6.25 * height in cm) - (5 * age in years) - 161
2. Activity Level Adjustment:
Your BMR is then multiplied by an activity factor to account for your daily physical activity:
Sedentary: BMR x 1.2
Lightly Active: BMR x 1.375
Moderately Active: BMR x 1.55
Very Active: BMR x 1.725
Extra Active: BMR x 1.9
This gives you your Total Daily Energy Expenditure (TDEE) if you were not pregnant.
3. Pregnancy Calorie Adjustments:
During pregnancy, calorie needs increase to support the growing fetus, placenta, and maternal tissue. These increases are generally:
First Trimester: Minimal increase, often around +0 to +100 kcal/day. Many women don't need extra calories yet, focusing on nutrient density.
Second Trimester: Approximately +340 kcal/day.
Third Trimester: Approximately +450 kcal/day.
This calculator adds these recommended extra calories to your adjusted TDEE based on the selected trimester.
How to Use the Calculator
To get your estimated daily calorie needs:
Enter your Age in years.
Input your Pre-Pregnancy Weight in kilograms. It's important to use your weight before you became pregnant for the most accurate BMR calculation.
Provide your Height in centimeters.
Select your typical Activity Level from the dropdown menu. Be honest about your daily routine.
Choose the current Trimester of your pregnancy.
Click the "Calculate Daily Calorie Needs" button.
Important Considerations
Nutrient Density: While calorie intake is important, the quality of those calories matters even more. Focus on whole foods rich in vitamins, minerals, protein, and healthy fats.
Individual Variation: Every pregnancy is unique. Factors like metabolism, multiple births, and specific health conditions can influence calorie needs.
Listen to Your Body: Hunger and fullness cues are valuable guides.
Consult a Professional: This calculator provides an estimate. Always consult with your healthcare provider or a registered dietitian for personalized dietary advice during pregnancy. They can assess your specific needs and ensure a healthy pregnancy for you and your baby.
function calculateCalories() {
var age = parseFloat(document.getElementById("age").value);
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var activityLevel = parseFloat(document.getElementById("activityLevel").value);
var trimester = parseInt(document.getElementById("trimester").value);
var resultValueElement = document.getElementById("result-value");
var additionalCaloriesElement = document.getElementById("additional-calories");
// Clear previous results and error messages
resultValueElement.textContent = "– kcal";
additionalCaloriesElement.textContent = "";
// Input validation
if (isNaN(age) || age <= 0 ||
isNaN(weight) || weight <= 0 ||
isNaN(height) || height <= 0 ||
isNaN(activityLevel) || activityLevel <= 0 ||
isNaN(trimester) || trimester 3) {
alert("Please enter valid positive numbers for age, weight, and height, and select valid options.");
return;
}
// 1. Calculate BMR using Mifflin-St Jeor equation for women
var bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161;
// 2. Calculate TDEE (Total Daily Energy Expenditure) based on activity level
var tdee = bmr * activityLevel;
// 3. Add extra calories based on trimester
var additionalCalories = 0;
if (trimester === 1) {
additionalCalories = 0; // Minimal increase, often negligible or focused on nutrient density
} else if (trimester === 2) {
additionalCalories = 340;
} else if (trimester === 3) {
additionalCalories = 450;
}
var totalDailyCalories = tdee + additionalCalories;
// Display the result
resultValueElement.textContent = Math.round(totalDailyCalories) + " kcal";
// Display additional calories info
var trimesterText = "";
if (trimester === 1) trimesterText = "First Trimester";
else if (trimester === 2) trimesterText = "Second Trimester";
else if (trimester === 3) trimesterText = "Third Trimester";
additionalCaloriesElement.textContent = "Based on your inputs, you need approximately " + additionalCalories + " extra calories per day during the " + trimesterText + ".";
}