Pre-pregnancy BMI calculator
Your pre-pregnancy BMI, and what it’s for.
Your weight gain range starts from your BMI before pregnancy. Work it out here.
Pre-pregnancy BMI
23.3
That’s in the healthy weight range (18.5 to 24.9). For one baby, the guideline total gain for this range is 25 to 35 lb.
BMI is a screening number, not a measure of health. Use the weight from before you were pregnant, not today’s.
In the Alma app
Pregnancy nutrition, set up for you.
- Choose Pregnancy nutrition as your goal.
- Alma turns calorie counting off by default and applies pregnancy nutrient targets.
- Caffeine starts at a 200 mg daily default.
- Alma’s coach never suggests fasting or a calorie deficit.
Questions
What people ask
Why does pre-pregnancy BMI matter?
The Institute of Medicine sets pregnancy weight gain ranges by BMI before pregnancy. Your BMI picks which range applies to you.
Can I use my current weight?
No. Weight during pregnancy includes the baby, placenta, fluid and extra blood. Use your weight from just before you became pregnant.
What are the BMI ranges?
Below 18.5 is underweight, 18.5 to 24.9 is healthy weight, 25.0 to 29.9 is overweight, and 30.0 or more is obese. These are the WHO cutoffs used in the 2009 guidelines.
Is BMI accurate?
BMI is a quick screening tool. It doesn’t measure body fat or health directly. Your care team looks at much more than one number.
Sources
Written by Alma from the primary sources below and reviewed November 13, 2026. This is general information, not medical advice. Your care team knows your pregnancy, so check questions with them. Editorial standards
Eat well for two, without the guesswork.
Choose Pregnancy nutrition as your goal, and Alma applies pregnancy nutrient targets to every meal you log.