Pregnancy Weight Gain Calculator
Calculate recommended pregnancy weight gain by week based on pre-pregnancy BMI.
Recommended Total Gain
25-35 lbs
Expected Gain by Now
8.9-12.5 lbs
Remaining to Gain
12.5-26.1 lbs
Pregnancy Weight Gain Details
| Pre-Pregnancy BMI | 23.3 |
| BMI Category | Normal |
| Pregnancy Type | Singleton |
| Weekly Rate Recommendation | 0.63-1.30 lbs/week |
| 1st Trimester (weeks 1-12) | 2.5-3.5 lbs |
| 2nd Trimester (weeks 13-26) | 11.3-15.8 lbs |
| 3rd Trimester (weeks 27-40) | 11.3-15.8 lbs |
Based on IOM (Institute of Medicine) guidelines. Consult your healthcare provider for personalized advice.
Use the Pregnancy Weight Gain Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.
Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.
How It Works
Our Pregnancy Weight Gain Calculator helps expectant mothers track their recommended weight gain throughout each week of pregnancy, personalized to their pre-pregnancy Body Mass Index (BMI). This tool is crucial for ensuring a healthy pregnancy for both mother and baby, aligning with the latest 2026 guidelines for optimal fetal development and maternal well-being.
The calculator utilizes the Institute of Medicine (IOM) guidelines, which stratify recommended weight gain based on pre-pregnancy BMI (underweight, normal weight, overweight, obese). It then distributes this total recommended gain across the trimesters, typically with minimal gain in the first trimester and a more consistent weekly gain in the second and third trimesters, adjusted for singleton pregnancies.
Remember that these are guidelines, and individual needs may vary; always consult your healthcare provider for personalized advice. A common mistake is focusing solely on the total weight gain without considering the weekly progression, which can lead to unnecessary anxiety or unhealthy practices.
Example: Normal Weight Pregnancy
- 1 A woman with a pre-pregnancy weight of 130 lbs and a height of 5'4" (BMI 22.3) is 18 weeks pregnant.
- 2 Based on her normal pre-pregnancy BMI, the calculator determines a recommended total weight gain of 25-35 lbs. For week 18, it calculates an expected gain of approximately 10-14 lbs.
- 3 At 18 weeks pregnant, her recommended weight gain range is 10-14 lbs from her pre-pregnancy weight.
- 4 This means if she started at 130 lbs, her current weight should ideally be between 140-144 lbs to be within the healthy range for this stage of pregnancy.
Source: CDC · Last updated: April 2026
Frequently Asked Questions
How much weight should I gain during pregnancy?
How much weight should I gain per week during pregnancy?
Where does pregnancy weight gain go?
You might also need
HSA Calculator 2026 — Contribution Limits & Triple Tax Savings
Calculate HSA tax savings, investment growth, and projected balance at retirement. See the triple tax advantage in action. Based on 2026 IRS contribution limits.
BMI Calculator — Body Mass Index, Category & Healthy Range
Calculate your Body Mass Index (BMI) from height and weight. See your BMI category, healthy weight range, and what it means. Free, instant results with chart.
Calorie Calculator (TDEE)
Calculate daily calories for maintenance, weight loss, or gain using the Mifflin-St Jeor equation and your activity level.