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Data sources and method

Conversions

One inch is exactly 2.54 cm by international definition, so conversions are exact. Feet-and-inches values are shown to one decimal place of an inch, and rounded to the nearest whole inch where a short form (such as 5′9″) is given.

Percentiles and averages

US figures come from the National Center for Health Statistics report Anthropometric Reference Data for Children and Adults: United States, 2015–2018 (Vital and Health Statistics, Series 3, No. 46), Tables 9 and 11. Heights were measured by trained examiners in the National Health and Nutrition Examination Survey, not self-reported. The report publishes the 5th, 10th, 15th, 25th, 50th, 75th, 85th, 90th and 95th percentiles; we interpolate in a straight line between them and do not estimate beyond the 5th or 95th.

Healthy weight

Healthy-weight ranges use the adult body mass index range of 18.5 to 24.9 used by the CDC and the World Health Organization. BMI is a screening measure, not a diagnosis.