Step by step
- Do not use adult BMI categories to evaluate weight gain while pregnant.
- Ask your doctor or midwife what healthy weight gain range applies to you.
- If you know your pre-pregnancy weight, choose kg / cm or lb / ft in. in the calculator on this page.
- Enter your pre-pregnancy weight and height to see your baseline BMI and WHO category.
At a glance
| Situation | What to use | Why |
|---|---|---|
| Currently pregnant | Prenatal weight gain charts | Accounts for baby, placenta, and fluid |
| Pre-pregnancy baseline | Adult BMI calculator | Helps doctors set weight gain goals |
| After pregnancy | Medical follow-up | Tracks recovery safely over time |
Related questions
Does the BMI calculator on this page work during pregnancy?
No. As noted in the tool details, BMI is not used to judge weight in pregnancy, so consult a health professional.
Why does BMI go up during pregnancy?
Weight naturally increases from the growing baby, amniotic fluid, placenta, and extra blood volume, which BMI cannot separate from body fat.
What should I ask my doctor instead of checking BMI?
Ask what total weight gain range is healthy for your pregnancy based on your pre-pregnancy weight and health history.
More questions: bmi calculator
- How to Calculate BMI
- What Is BMI?
- What Is a Healthy BMI?
- What Weight Should I Be for My Height?
- Is the BMI Calculator Different for Women and Men?
- Can BMI Be Used for Children and Teens?
- How Does BMI Apply to Seniors?
- Why Is My BMI High When I Have Muscle?
- BMI Calculator vs. Body Fat Percentage: Which Should You Use?
- How to Check Your BMI on an iPhone Without an App
- How to Use a BMI Calculator in kg and Feet or cm
Open the full bmi calculator →
Updated November 14, 2026.