Calculate % change from birth weight for days 0–14, compare against a typical curve, and estimate when baby returns to birth weight.

https://devonwheels.com/tools/newborn-weight-change/embed

About the Newborn Weight Change Tracker

The Newborn Weight Change Tracker helps you calculate the percent change from birth weight and compare it with the typical newborn weight pattern in the first 2 weeks. Most babies lose a small percentage of their birth weight before regaining it, usually within the first 10–14 days.

What’s Typical (Guidance Only)

• Day 3–4 (nadir): Many newborns are 3–7% below birth weight.
• By ~day 10: Most babies return to about their birth weight.
• Caution threshold: A weight loss of ≥10% is often flagged as a reason to contact a healthcare provider.

How It Works

1. Enter your baby’s birth weight and current weight (kg or lb).
2. Enter the day of life (0 = birthday).
3. The tool calculates % change from birth weight and compares it with the expected range.
4. You’ll see your baby’s data point on the chart, along with a −10% reference line for safety.

Example

• Birth weight: 3.40 kg
• Current weight (day 3): 3.20 kg
• Formula: ((3.20 − 3.40) ÷ 3.40) × 100 = −5.9%
• Result: Within the normal range for day 3.