6 MONTH REFERENCE · KG
6-month-old baby weight percentile
This is a useful age to review the full series of measurements. The reference median below is a comparison value, not a target for feeding or growth.
Typical weight at 6 months
At 183 days, the WHO median is 7.30 kg for girls and 7.94 kg for boys. These are reference medians, not target weights.
Weight reference at 183 days
Values below are in kg. The columns are reference percentiles, not recommended limits. “6 months” is represented here by 183 days (30.4375 days per month, rounded). Calendar age may differ; use exact dates in the calculator.
| WHO reference | 3rd | 25th | 50th | 75th | 97th |
|---|---|---|---|---|---|
| Girls | 5.82 | 6.73 | 7.30 | 7.93 | 9.20 |
| Boys | 6.44 | 7.37 | 7.94 | 8.54 | 9.73 |
How to use this table
Find the row for the sex used in your baby’s growth record, then compare the measurement in kg. Between two columns means between those reference percentiles. The calculator gives a more precise comparison using daily WHO parameters.
Measure weight consistently
Use a baby scale on a stable, level surface. Record the measurement and date as accurately as possible, and keep clothing and weighing conditions consistent between visits.
What this comparison cannot tell you
A weight percentile alone cannot tell you whether a baby is underweight or overweight. Length, feeding, medical history and the pattern over time also matter. The number does not diagnose a condition or establish a growth goal.
Read the weight percentile guide or browse other ages and measurements.
Source: WHO Child Growth Standards, expanded daily tables. Values derived with the LMS method and rounded to two decimals. Methodology and limitations.
WORKED EXAMPLE
Use the date, not the label
Two babies both described as “six months old” may differ by several weeks. Entering exact dates selects the appropriate daily WHO parameters and avoids assigning both to the same approximate age.
A better six-month comparison
| Input | Why it matters | Measurement tip |
|---|---|---|
| Exact dates | Selects the daily WHO reference. | Copy from the health record. |
| Weight | Provides weight-for-age. | Use a level baby scale. |
| Recumbent length | Adds length-for-age and weight-for-length. | Measure lying down, head to heel. |
Questions parents ask
Is six months always 183 days?
No. Calendar months vary. This reference page uses 183 days, while the calculator uses exact birth and measurement dates.
Should a baby be near the 50th percentile?
Not necessarily. The median is a reference midpoint, not an individual target.
What if today’s result differs from the last visit?
First check dates, units and measuring conditions. A professional can interpret a confirmed change in the context of the child’s full history.
Review status: Maintained by Baby Growth and technically reviewed on 29 September 2026. Calculations and product ranges are checked against the cited WHO, CDC and manufacturer sources. This independent tool has not received clinical review and does not replace professional care.