Pregnancy Weight Gain Calculator
Track recommended weight gain during pregnancy
Based on IOM guidelines. Consult your OB-GYN.
About Pregnancy Weight Gain Calculator
Gaining the right amount of weight during pregnancy is essential for both maternal and fetal health. This free pregnancy weight gain calculator helps you determine the recommended weight gain range based on your pre-pregnancy BMI and current week of pregnancy. It follows the Institute of Medicine (IOM) guidelines endorsed by the American College of Obstetricians and Gynecologists to provide evidence-based recommendations.
Weight gain during pregnancy supports your baby's growth and development, the formation of the placenta, increased blood volume, amniotic fluid, and energy stores for breastfeeding. Gaining too little weight can increase the risk of preterm birth and low birth weight, while gaining too much may lead to gestational diabetes, preeclampsia, and complications during delivery. Tracking your progress helps you stay within the healthy range recommended for your body type.
All calculations are performed entirely in your browser. No personal health data is collected, stored, or sent to any server. This tool is for educational purposes and should not replace the guidance of your healthcare provider, who can offer personalized advice based on your complete health profile.
How to Use
- Enter your pre-pregnancy weight and height to calculate your BMI
- Select your current week of pregnancy
- Indicate if you are carrying a single baby or twins
- Click Calculate to see your recommended weight gain range
- Review the trimester-by-trimester breakdown of expected gains
Weight Gain Guidelines by BMI Category
The IOM recommends different weight gain ranges based on pre-pregnancy BMI. Underweight women (BMI below 18.5) should aim for 28-40 pounds total. Normal weight women (BMI 18.5-24.9) should target 25-35 pounds. Overweight women (BMI 25-29.9) are advised to gain 15-25 pounds, and obese women (BMI 30 or above) should limit gain to 11-20 pounds. For twin pregnancies, these ranges are significantly higher.
Why Use Pregnancy Weight Gain Calculator?
- Evidence-based recommendations following IOM guidelines
- Personalized ranges based on your pre-pregnancy BMI
- Week-by-week tracking throughout your pregnancy
- 100% free with no registration required
- Complete privacy with browser-only calculations
- Support for single and twin pregnancies