Calories for Two — With Precision

Pregnancy raises energy needs, but not by a flat amount. Your baseline is set by your age, height, pre-pregnancy weight, and activity; pregnancy adds a defined increment per trimester. This pregnancy calorie calculator uses the Mifflin-St Jeor equation with the ACOG trimester guidelines to produce a daily target you can actually use.

The ACOG Trimester Increments

The American College of Obstetricians and Gynecologists recommends no extra calories in the first trimester, about +340 per day in the second, and +452 per day in the third for a singleton pregnancy. Multiples add roughly 300 more per day per additional fetus. These numbers support the recommended 25–35 lb total gain for a normal starting BMI.

Guidance, Not a Prescription

Energy needs vary with body composition, medical conditions, and activity changes during pregnancy. Treat the calculator's number as a starting point and let your obstetric provider adjust it — especially if you are underweight, overweight, carrying multiples, or managing conditions like gestational diabetes.