🤰 Pregnancy Calorie Needs: Calculator

Estimate your daily calorie needs by trimester using BMR and ACOG guidance.

kg
cm
yrs
TOTAL DAILY CALORIE NEEDS
0 kcal
for your current trimester and activity level
BMR
0 kcal
TDEE (Maintenance)
0 kcal
Trimester Addition
+0 kcal
Trimester
2nd
BMR (Mifflin-St Jeor, women) + ACOG-published trimester calorie additions

How the Pregnancy Calorie Needs Calculator Works

This calculator estimates your total daily calorie needs during pregnancy by first calculating your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, multiplying it by an activity factor to get your maintenance calories (TDEE), and then adding the standard trimester-specific calorie increase published by the American College of Obstetricians and Gynecologists (ACOG).

BMR (women) = 10 × Weight (kg) + 6.25 × Height (cm) − 5 × Age − 161
TDEE = BMR × Activity Multiplier
Total Calorie Needs = TDEE + Trimester Addition

ACOG Trimester Calorie Additions

According to standard ACOG guidance, calorie needs don't increase in the first trimester, but rise by roughly 340 kcal/day in the second trimester and roughly 450 kcal/day in the third trimester, reflecting the growing energy demands of pregnancy. These additions are added on top of your pre-pregnancy maintenance calories (TDEE), not on top of a generic baseline.

Use This as a Starting Point, Not a Prescription

Every pregnancy is different, and factors like carrying multiples, pre-pregnancy weight status, gestational diabetes, or other medical conditions can significantly change your actual calorie needs. This calculator provides a general, formula-based estimate; always follow the personalized guidance of your OB-GYN or a registered dietitian for your specific pregnancy.

📎 Related Tools: Pregnancy Due Date Calculator Pregnancy Calculator BMR Calculator TDEE Calculator

❓ Frequently Asked Questions

How many extra calories do I need during pregnancy?
Standard ACOG guidance suggests no extra calories are needed in the first trimester, about 340 extra calories/day in the second trimester, and about 450 extra calories/day in the third trimester, added on top of your pre-pregnancy maintenance calories.
Why does this calculator use my pre-pregnancy weight instead of my current weight?
Using pre-pregnancy weight for the BMR calculation follows standard clinical practice, since using current (increasing) pregnancy weight would compound the pregnancy weight gain into the BMR estimate rather than accounting for it separately through the trimester addition.
Is this calculator safe to use if I'm carrying twins or multiples?
This calculator uses the standard single-pregnancy ACOG addition and does not account for multiples, which typically require a higher calorie intake. If you're pregnant with multiples, work directly with your OB-GYN or a registered dietitian for personalized calorie targets.
What is the Mifflin-St Jeor equation?
It's one of the most widely validated equations for estimating Basal Metabolic Rate (BMR) — the calories your body burns at complete rest. It's commonly used in clinical and research settings as a more accurate alternative to older formulas like Harris-Benedict.
Should I follow this calculator's number exactly every day?
Treat it as a general daily target rather than an exact prescription. Appetite, nausea (especially in the first trimester), and individual medical circumstances all affect actual intake — always discuss your specific nutritional needs with your prenatal care provider.

🏆 About This Tool — Accuracy & Trust

🔒 Data Privacy: All calculations run entirely within your browser using JavaScript. Nothing you enter here is ever transmitted to our servers, stored, sold, or shared.

📐 Accuracy Note: This tool uses standard, widely published formulas and guidelines. Results are estimates for informational purposes; for financial, medical, or engineering decisions, consult a licensed professional.

📅 Last Updated: September 2026.