Sydney is about 9 times smaller than Arlington.

Arlington is approximately 248 sq km, while Sydney is approximately 27 sq km, making Sydney 10.76% the size of Arlington.
Tip: This to-scale comparison of Arlington vs. Sydney 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.