It's generally recommended you allow 2 to 2.5 hours of time in between your connecting flights. And, for those of you who are connecting within Australia, you will need to clear customs and immigration, so it's recommended you allow some extra time for a stress-free beginning to your trip.
By breaking up your flight into a multi-city route, many airlines will permit you to stay for free (termed "free stopover") in the connection city. Some of the most popular cities for stopovers en route to Australia include Singapore, Fiji, Hawaii, Hong Kong, and Kuala Lumpur, Malaysia.
Example Stopover | Important Note
Example: San Francisco to Sydney, with 7 day free stopover in Nadi, Fiji.