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

Tajikistan:
slightly smaller than Wisconsin

Tanzania:
slightly larger than twice the size of California

Thailand:
slightly more than twice the size of Wyoming

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