| Rank | Country | Median age |
203 | Afghanistan |  total: 17.6 years male: 17.6 years female: 17.6 years (2008 est.) |
| Akrotiri | void |
89 | Albania |  total: 29.5 years male: 28.9 years female: 30.2 years (2008 est.) |
117 | Algeria |  total: 26 years male: 25.8 years female: 26.2 years (2008 est.) |
134 | American Samoa |  total: 24 years male: 23.9 years female: 24.2 years (2008 est.) |
6 | Andorra |  total: 42.1 years male: 42.3 years female: 41.9 years (2008 est.) |
196 | Angola |  total: 18 years male: 18 years female: 18 years (2008 est.) |
74 | Anguilla |  total: 32.3 years male: 31.3 years female: 33.4 years (2008 est.) |
| Antarctica | void |
82 | Antigua and Barbuda |  total: 30.5 years male: 30 years female: 31.1 years (2008 est.) |
| Arctic Ocean | void |
84 | Argentina |  total: 30.3 years male: 29.3 years female: 31.3 years (2008 est.) |
80 | Armenia |  total: 31.1 years male: 28.4 years female: 34 years (2008 est.) |
46 | Aruba |  total: 37.6 years male: 35.8 years female: 39.3 years (2008 est.) |
| Ashmore and Cartier Islands | void |
| Atlantic Ocean | void |
49 | Australia |  total: 37.4 years male: 36.6 years female: 38.3 years (2008 est.) |
9 | Austria |  total: 41.7 years male: 40.7 years female: 42.8 years (2008 est.) |
105 | Azerbaijan |  total: 27.9 years male: 26.3 years female: 29.7 years (2008 est.) |
100 | Bahamas, The |  total: 28.4 years male: 27.6 years female: 29.2 years (2008 est.) |
86 | Bahrain |  total: 29.9 years male: 33 years female: 26.4 years (2008 est.) |
142 | Bangladesh |  total: 22.8 years male: 22.8 years female: 22.9 years (2008 est.) |
61 | Barbados |  total: 35.4 years male: 34.2 years female: 36.4 years (2008 est.) |
40 | Belarus |  total: 38.4 years male: 35.4 years female: 41.3 years (2008 est.) |
12 | Belgium |  total: 41.4 years male: 40.2 years female: 42.7 years (2008 est.) |
170 | Belize |  total: 20.1 years male: 20 years female: 20.3 years (2008 est.) |
198 | Benin |  total: 17.9 years male: 17.5 years female: 18.3 years (2008 est.) |
17 | Bermuda |  total: 41 years male: 40.1 years female: 41.8 years (2008 est.) |
138 | Bhutan |  total: 23.5 years male: 24.1 years female: 22.8 years (2008 est.) |