Free Carely Tool

Pregnancy Weight Gain Calculator

Find your pre-pregnancy BMI category and the recommended total weight gain range during pregnancy, based on Institute of Medicine (IOM) guidelines.

Pregnancy weight gain

Recommended total weight gain

This is an estimate, not medical advice. Recommended weight gain varies with your health, number of babies and other factors — confirm with your doctor.

Frequently asked questions

How much weight should I gain during pregnancy?

It depends on your pre-pregnancy BMI: 12.5–18 kg if underweight, 11.5–16 kg if normal, 7–11.5 kg if overweight, and 5–9 kg if obese (single baby, IOM guidelines).

How is pre-pregnancy BMI calculated?

BMI is weight in kilograms divided by height in metres squared (kg ÷ m²), which sets your recommended weight gain range.