Pregnancy Weight Gain Calculator
Track recommended weight gain week by week during pregnancy.
Tip: In the first trimester normal gain is only 0.5–2 kg in total — most of the gain happens in the second and third trimesters (about 0.4 kg/week).
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About this digital tool
The pregnancy weight gain calculator compares your actual gain with the recommended range for your week of pregnancy. Enter your pre-pregnancy weight, height, current weight and the week, and get your pre-pregnancy BMI, the category and the expected gain to this week.
Recommendations depend on pre-pregnancy BMI: women who are underweight are advised to gain more, those who are overweight less. In the first trimester gain is usually small, while after it the pace picks up. Every pregnancy is different (twins, illness, severe nausea), so the range is only a guide. The result is for information and does not replace check-ups. Your gynaecologist is the right person to set your weight goal.
How to use
- Enter the date of your last period
- Enter your pre-pregnancy weight
- Enter your height
- Enter your current weight
- See the progress chart and recommendations
Frequently asked questions
How much weight should I gain during pregnancy?
It depends on your pre-pregnancy BMI: Underweight (BMI <18.5): 12.5–18 kg. Normal weight (18.5–24.9): 11.5–16 kg. Overweight (25–29.9): 7–11.5 kg. Obesity (≥30): 5–9 kg.
Is excess gain dangerous?
Yes, excess gain increases the risk of gestational diabetes, pre-eclampsia, caesarean birth and difficulty losing weight after birth.
Where does the extra weight go?
Baby: 3–3.5 kg, placenta: 0.7 kg, amniotic fluid: 0.8 kg, uterus: 0.9 kg, breasts: 0.5 kg, extra blood: 1.2 kg, fluids: 1.2 kg, fat stores: 2.5–4 kg.
How is the expected weight gain during pregnancy calculated?
The calculator uses pre-pregnancy BMI to choose the total gain range and spreads it according to the week of pregnancy, with small gain in the first trimester.
What if I'm outside the range?
Don't worry about a single result; weigh-ins vary. If you are consistently above or below the range, talk to your gynaecologist, who can assess your diet and health.