Pregnancy Weight Gain Calculator
Calculated in your browser — we never store your dataPeer-reviewed formulas (Mifflin-St Jeor, WHO)
Medical Disclaimer: This calculator provides general guidelines based on IOM (Institute of Medicine) recommendations. Every pregnancy is different. Always consult your OB-GYN or midwife for personalized guidance on healthy weight gain during pregnancy.
On Track
You've gained 10.0 lbs. The recommended range at 20 weeks is 7.6 - 11.4 lbs.
This calculator provides estimates for informational purposes only. It is not medical advice. Consult a healthcare professional before making health decisions.
IOM Recommended Weight Gain by BMI (2026 Guidelines)
| BMI Category | BMI Range | Total Gain |
|---|---|---|
| Underweight | < 18.5 | 28-40 lbs |
| Normal (You) | 18.5-24.9 | 25-35 lbs |
| Overweight | 25-29.9 | 15-25 lbs |
| Obese | 30+ | 11-20 lbs |
Weight Gain by Trimester
1st Trimester (Weeks 1-13)2-4.4 lbs
Minimal gain expected. Focus on nutrition quality, not quantity.
2nd Trimester (Weeks 14-26)0.8-1 lbs/week
Steady gain begins. Baby is growing rapidly.
3rd Trimester (Weeks 27-40)0.8-1 lbs/week
Continued steady gain. Baby gains most weight in the last 8 weeks.
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