Texas is about 1.4 times smaller than South Australia.

South Australia is approximately 984,321 km² (380,048 sq mi), while Texas is approximately 678,052 sq km, making Texas 68.89% the size of South Australia.
Tip: This to-scale comparison of South Australia vs. Texas uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.