Compare your pre-pregnancy BMI and current weight gain with full-pregnancy weight-gain ranges for singleton or twin pregnancy.
Pregnancy weight goals require individualized prenatal care. This tool reports published total pregnancy ranges and does not determine whether your current week-by-week gain is medically appropriate.
The ranges this calculator reports come from the Institute of Medicine's 2009 guidelines, still the standard reference used by obstetric providers. The key idea: your recommended total depends on your pre-pregnancy BMI, not on a single number for everyone.
| Pre-Pregnancy BMI | Singleton: Total Gain | Twins: Total Gain |
|---|---|---|
| Underweight (below 18.5) | 28–40 lb (12.5–18 kg) | — |
| Normal weight (18.5–24.9) | 25–35 lb (11.5–16 kg) | 37–54 lb (16.8–24.5 kg) |
| Overweight (25–29.9) | 15–25 lb (7–11.5 kg) | 31–50 lb (14–22.7 kg) |
| Obese (30 and above) | 11–20 lb (5–9 kg) | 25–42 lb (11.3–19 kg) |
Pacing matters too. In the first trimester most people gain just 1–4 lb total. The steady climb happens in the second and third trimesters: roughly 1 lb per week for a normal pre-pregnancy BMI, about 0.6 lb per week if overweight, and about 0.5 lb per week if obese. Gaining too little is linked with low birth weight; gaining far too much raises the odds of gestational diabetes, high blood pressure, and delivery complications — which is exactly why steady tracking beats a single weigh-in.
Note what these ranges are not: they are population guidelines, not a personal prescription. Your provider may adjust them for your height, age, health history, or a multiple pregnancy. The American College of Obstetricians and Gynecologists publishes a clear one-page infographic on the same ranges that many clinics hand out at the first prenatal visit.
Pregnancy weight goals require individualized prenatal care. This tool reports published total-pregnancy ranges; it cannot tell you whether your week-by-week gain is medically appropriate. Bring your trend to your OB-GYN or midwife — that conversation is what the numbers are for.
Maintained by Live Fitness Check. Last updated: August 13, 2026. How we test our calculators .
Published recommendations use pre-pregnancy BMI and whether the pregnancy is singleton or twin.
No. It reports the recommended total range for the entire pregnancy and your current change from pre-pregnancy weight.
The calculator does not support higher-order multiple pregnancy. Discuss an individualized weight-gain plan with your prenatal care team.
