See the healthy pregnancy weight-gain range for your pre-pregnancy BMI, based on IOM/CDC guidelines, with typical gain by week. A supportive general guide — not a target — to discuss with your provider.
This shows the general healthy weight-gain range recommended in pregnancy guidelines (IOM/CDC), based on pre-pregnancy BMI. It’s a guide, not a target to police — every pregnancy is different. Pregnancy is not a time for dieting; your midwife or doctor will advise what’s right for you.
About you
kg
cm
of 40
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Pre-pregnancy weight and height set your starting BMI category, which the guidelines use to suggest a healthy total gain. Twins and other situations follow different advice — check with your provider.
Recommended total gain
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Enter your details
Pre-pregnancy BMI
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BMI category
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Typical gain by this week
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Your gain so far
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General guidance from IOM/CDC ranges, not medical advice and not a personal target. If weight or eating in pregnancy worries you, that’s worth talking through with your midwife or doctor, who can give individual, supportive guidance.
Use this free pregnancy weight gain calculator to see the healthy weight-gain range recommended in pregnancy, based on your pre-pregnancy BMI. It’s a supportive guide, not a target to police.
What this pregnancy weight gain calculator does
This pregnancy weight gain calculator uses the widely used IOM/CDC guidelines to show a healthy total gain range for your pre-pregnancy BMI, plus the typical gain so far by your current week. It’s general information to discuss with your provider — not a strict rule.
Recommended weight gain by pre-pregnancy BMI
Pre-pregnancy BMI
Recommended total gain
Underweight (under 18.5)
12.7–18.1 kg (28–40 lb)
Healthy weight (18.5–24.9)
11.3–15.9 kg (25–35 lb)
Overweight (25–29.9)
6.8–11.3 kg (15–25 lb)
Obese (30+)
5.0–9.1 kg (11–20 lb)
These are for a single baby. Twins and other situations follow different guidance.
How gain is spread across pregnancy
Most gain happens in the second and third trimesters. The first trimester typically adds only a small amount (around 0.5–2 kg / 1–4 lb), then a steadier weekly increase follows. Some weeks more, some less — the overall trend matters more than any single week.
A gentle note on weight in pregnancy
Pregnancy is not a time for dieting or weight loss — your body and baby need steady nourishment. Ranges like these are a general guide, and what’s right varies from person to person. If thinking about weight or eating feels stressful, please bring it to your midwife or doctor, who can offer kind, individual support.
How to use the pregnancy weight gain calculator
Enter your pre-pregnancy weight and height.
Add your current week (and current weight, if you like).
See the recommended total range and the typical gain by now.
Pregnancy Weight Gain FAQ
How much weight should I gain in pregnancy?
It depends on your pre-pregnancy BMI. Guidelines suggest about 11.3–15.9 kg (25–35 lb) for a healthy starting weight, with different ranges if you began under- or overweight. The calculator shows your range.
How is the recommended range worked out?
From your pre-pregnancy BMI, using the IOM/CDC categories. The calculator finds your BMI from your starting weight and height, then applies the matching range.
How is weight gain spread across pregnancy?
The first trimester usually adds a small amount (around 0.5–2 kg / 1–4 lb), with steadier weekly gain in the second and third trimesters. The overall trend matters more than any single week.
Should I try to lose weight or diet while pregnant?
No — pregnancy isn't a time for dieting or intentional weight loss. Your body and baby need steady nourishment. Any concerns about weight should go to your midwife or doctor.
What if my gain is outside the range?
Being a little above or below is common and often fine. These ranges are a general guide, not a strict rule. Your provider looks at the whole picture and advises what's right for you.
Is the pregnancy weight gain calculator free?
Yes, this pregnancy weight gain calculator is completely free, needs no sign-up, and gives instant results in your browser.
