What Is the Average Weight for a 6 Month Old?
The average weight for a 6 months is 7.9 kg for boys and 7.3 kg for girls. These are WHO reference medians. The healthy range (3rd–97th percentile) is approximately 6.4–9.7 kg for both sexes at this age.
| Sex | Median Weight | Healthy Range | Median Height | Healthy Height Range |
|---|---|---|---|---|
| Boys | 7.9 kg | 6.4–9.7 kg | 67.6 cm | 63–72 cm |
| Girls | 7.3 kg | 6.4–9.7 kg | 65.7 cm | 63–72 cm |
Head Circumference at 6 months
6 months head circumference reflects brain growth.
| Sex | Median HC | Healthy Range |
|---|---|---|
| Boys | 43.3 cm | 41–46 cm |
| Girls | 42.2 cm | 41–46 cm |
What Is the Average Height for a 6 Month Old?
The average height for a 6 months is 67.6 cm for boys and 65.7 cm for girls. The normal height range is 63–72 cm. Growth should track along a consistent percentile. Significantly slower growth (crossing 2+ major percentile lines) may need evaluation.
How to Interpret Your Child's Measurements
- The percentile tells you what percentage of healthy children of the same age and sex are smaller (or lighter) than your child
- A measurement at the 50th percentile matches the WHO median — this is the average
- Any measurement between the 3rd and 97th percentiles is within the normal, healthy range
- What matters most is consistent growth along a percentile curve, not the absolute number
If your child’s height or weight deviates significantly from the median (z-score below -2 or above +2), consult your paediatrician. However, a single measurement point is much less informative than the overall growth trend.
Growth Expectations at 6 months
At 6 months, growth continues at a steady pace as part of the normal childhood growth pattern. Consistency along a percentile curve is the best indicator of healthy growth.
Frequently Asked Questions
What is the average weight for a 6 months?
The average weight for a 6 months is 7.9 kg (17 lb) for boys and 7.3 kg (16 lb) for girls. The healthy range is approximately 6.4–9.7 kg. Both WHO and CDC consider any weight between the 3rd and 97th percentiles as within the normal range.
What is the average height for a 6 months?
The average height for a 6 months is 67.6 cm for boys and 65.7 cm for girls. The normal range is 63–72 cm. Growth should follow a consistent percentile curve.
Should I worry if my child is above or below average?
Not necessarily. Being above or below the average is completely normal. The WHO considers any measurement between the 3rd and 97th percentiles as within the healthy range. What matters far more than a single measurement is whether your child is growing consistently along their own percentile curve.
How much weight should a 6 months gain?
Children at 6 months typically gain weight steadily. If your child consistently follows their own growth curve (even if it is below the average), that is generally a positive sign. Consult your paediatrician if you notice significant weight loss or a flat growth curve over 3+ months.
Can I track my child's growth over time?
Yes! GrowChart lets you log height, weight, and head circumference measurements over time and plots them automatically on WHO percentile curves. You can see the trend, share reports with your paediatrician, and get AI-powered insights. Start free here.
Track growth with automated WHO charts
Log measurements once and GrowChart plots everything on clinical-grade percentile curves. Free for all users.