| Country | Area - comparative |
| Sudan | slightly more than one-quarter the size of the US |
| Suriname | slightly larger than Georgia |
| Svalbard | slightly smaller than West Virginia |
| Swaziland | slightly smaller than New Jersey |
| Sweden | slightly larger than California |
| Switzerland | slightly less than twice the size of New Jersey |
| Syria | slightly larger than North Dakota |
| Taiwan | slightly smaller than Maryland and Delaware combined |
| Tajikistan | slightly smaller than Wisconsin |
| Tanzania | slightly larger than twice the size of California |
| Thailand | slightly more than twice the size of Wyoming |
| Timor-Leste | slightly larger than Connecticut |
| Togo | slightly smaller than West Virginia |
| Tokelau | about 17 times the size of The Mall in Washington, DC |
| Tonga | four times the size of Washington, DC |
| Trinidad and Tobago | slightly smaller than Delaware |
| Tunisia | slightly larger than Georgia |
| Turkey | slightly larger than Texas |
| Turkmenistan | slightly larger than California |
| Turks and Caicos Islands | 2.5 times the size of Washington, DC |
| Tuvalu | 0.1 times the size of Washington, DC |
| Uganda | slightly smaller than Oregon |
| Ukraine | slightly smaller than Texas |
| United Arab Emirates | slightly smaller than Maine |
| United Kingdom | slightly smaller than Oregon |
| United States | about half the size of Russia; about three-tenths the size of Africa; about half the size of South America (or slightly larger than Brazil); slightly larger than China; more than twice the size of the European Union |
| United States Pacific Island Wildlife Refuges | Baker Island: about two and a half times the size of The Mall in Washington, DC Howland Island: about three times the size of The Mall in Washington, DC Jarvis Island: about eight times the size of The Mall in Washington, DC Johnston Atoll: about four and a half times the size of The Mall in Washington, DC Kingman Reef: a little more than one and a half times the size of The Mall in Washington, DC Midway Islands: about nine times the size of The Mall in Washington, DC Palmyra Atoll: about 20 times the size of The Mall in Washington, DC |
| Uruguay | slightly smaller than the state of Washington |
| Uzbekistan | slightly larger than California |
| Vanuatu | slightly larger than Connecticut |
| Venezuela | slightly more than twice the size of California |
| Vietnam | slightly larger than New Mexico |
| Virgin Islands | twice the size of Washington, DC |
| Wake Island | about 11 times the size of The Mall in Washington, DC |
| Wallis and Futuna | 1.5 times the size of Washington, DC |
| West Bank | slightly smaller than Delaware |
| Western Sahara | about the size of Colorado |
| World | land area about 16 times the size of the US |
| Yemen | slightly larger than twice the size of Wyoming |
| Zambia | slightly larger than Texas |
| Zimbabwe | slightly larger than Montana |