Pregnancy Weight Gain Calculator
HealthEstimate a recommended total pregnancy weight gain range from your pre-pregnancy height and weight, based on commonly referenced IOM BMI-category guidelines.
Pre-Pregnancy BMI
23.9
Recommended Total Gain (Low)
11.5
Recommended Total Gain (High)
16
What is a Recommended Weight Gain?
The Pregnancy Weight Gain Calculator estimates a recommended total pregnancy weight gain range from your pre-pregnancy height and weight, based on commonly referenced IOM (Institute of Medicine) BMI-category guidelines.
For related weight and BMI tools, see the BMI Calculator and Pregnancy BMI Calculator.
How to use this Recommended Weight Gain calculator
- Enter your pre-pregnancy height in centimetres.
- Enter your pre-pregnancy weight in kilograms.
- Read your Pre-Pregnancy BMI and Recommended Total Gain range instantly.
- Discuss your personal weight gain target with your healthcare provider, who can factor in your complete health picture.
Formula & Methodology
Pre-Pregnancy BMI = Weight (kg) ÷ Height (m)² Recommended total gain by BMI category: Underweight (<18.5) → 12.5-18 kg; Normal (18.5-24.9) → 11.5-16 kg; Overweight (25-29.9) → 7-11.5 kg; Obese (30+) → 5-9 kg. Worked example — a pre-pregnancy height of 165 cm and weight of 65 kg: BMI = 65 ÷ (1.65)² = 23.9 (Normal category) Recommended Total Gain = 11.5-16 kg
Frequently Asked Questions
Recommended total weight gain depends on your pre-pregnancy BMI category — commonly cited IOM guidelines suggest roughly 12.5-18 kg for underweight, 11.5-16 kg for normal weight, 7-11.5 kg for overweight, and 5-9 kg for obese pre-pregnancy BMI categories.
Someone starting pregnancy with lower reserves is generally guided toward a higher total gain to support healthy fetal development, while someone starting with higher reserves is generally guided toward a lower total gain — reflecting different starting points for overall pregnancy health.
The calculator uses the standard BMI formula — weight in kilograms divided by height in metres squared — based on your entered pre-pregnancy height and weight.
The IOM (Institute of Medicine) guidelines are commonly referenced total pregnancy weight gain recommendations organized by pre-pregnancy BMI category, widely used as a general reference point in prenatal care discussions.
No — this calculator provides a general reference range based on commonly cited guidelines. Your healthcare provider can give personalized guidance based on your specific health history, including any factors that might warrant a different target.
No — this calculator uses guidelines designed for singleton pregnancies; twin and multiple pregnancies typically have different, generally higher, recommended weight gain ranges that aren't reflected in this calculator.
Weight gain patterns vary between individuals and pregnancies for many reasons; any concerns about your specific weight gain trajectory should be discussed with your healthcare provider, who can consider your complete situation.
This calculator uses the same BMI formula as the general [BMI Calculator](/bmi-calculator/), applied specifically to pre-pregnancy measurements to determine which weight gain guideline category applies.
This calculator provides a total recommended range for the full pregnancy; healthcare providers often also discuss expected gain pace by trimester, which isn't covered by this simplified total-range calculator.
Weight gain within a generally recommended range is one of several factors healthcare providers consider when monitoring a healthy pregnancy, alongside many other clinical indicators — this calculator provides a reference point only, not a complete assessment.
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