Typical height and growth left at 18
| Average height | Adult height reached | Typical growth left | |
|---|---|---|---|
| Boys | 5′9½″ · 176 cm | 100% | 1 cm · 0.3 in |
| Girls | 5′4″ · 163 cm | 100% | — |
Averages from CDC growth charts at exactly 18 years, compared with the chart's adult height at 20.
Boys at 18
Nearly all boys have finished growing; growth plates are closed or closing.
Girls at 18
Most girls have finished growing.
Why an average isn't your answer
Two 18-year-olds of the same height can end up at very different adult heights, because one has done most of their growing and the other hasn't started. Your parents' heights and your current weight tell the calculator which one you are likely to be, so your range is far tighter than any average.
