The speed limits on highways can vary between different countries and regions based on various factors such as road conditions, traffic density, safety considerations, and legal regulations. In Australia, the standard speed limit on many superhighways or freeways is indeed 100 kilometers per hour (km/h), which is equivalent to approximately 62 miles per hour (mph).
On the other hand, in the United States, the common speed limit on many highways, including interstate highways, is 65 mph (miles per hour), which is approximately 105 km/h.
It's important to note that these are general speed limits and may vary within different states or specific road sections based on local regulations. Additionally, there may be variations due to factors such as urban areas, construction zones, or specific road conditions, where lower speed limits could be imposed for safety reasons.
It's always essential to adhere to the posted speed limits and follow local traffic laws and regulations when driving in any country or region.