Get the recommended total weight-gain range for pregnancy based on your pre-pregnancy BMI.
What this calculator does
Recommended pregnancy weight gain depends on your starting BMI. Enter your pre-pregnancy weight and height and this calculator gives the Institute of Medicine range for a singleton pregnancy, plus a weekly guide for the second and third trimesters.
It’s general guidance — your provider can advise for your situation.
The default scenario, worked through
On the values this calculator opens with, the recommended total gain is 11.5–16 kg. Underneath, Pre-pregnancy BMI comes out at 22 and Category at Normal. Change any field and every figure updates as you type.
Getting your answer
- Enter your pre-pregnancy weight and height.
- Read your BMI category.
- See the recommended total and weekly gain.
Formula reference
ranges by pre-pregnancy BMI (IOM):
under 18.5: 12.5–18 kg · 18.5–24.9: 11.5–16 kg · 25–29.9: 7–11.5 kg · 30+: 5–9 kg
FAQ
How much weight should I gain?
It depends on your pre-pregnancy BMI. Normal-weight women are generally advised 11.5–16 kg for a single baby; other categories differ.
Is more or less gain risky?
Both too little and too much gain carry risks. Your provider can guide the right target for you.
Does this cover twins?
No — these ranges are for singleton pregnancies. Multiples have higher recommended gains.