But nearest neighbour New Zealand put the country to shame, with an average speed of 14.7mbps and a speed boost of 40 per cent since the same time last year.
Globally, South Korean internet users can access more than double the average speeds of Australian connections at 28.6mbps, as can Norwegians and Swedes.
Australia also ranked 47th in the world for connections over 15 megabits per second, with just under one in five internet users qualifying for the mark.
To put the speed in context, you need at least five megabits per second to stream high-definition shows from Netflix, and 25mbps for Ultra HD quality.
Australia's low ranking out of the 241 countries ranked for broadband performance comes despite the growing rollout of the National Broadband Network.
But an NBN Co spokesman said it was important to note the Akamai report covered "millions of people who don't yet have the NBN network".
NBN Co yesterday revealed more than five million Australian homes and businesses were ready to be connected to the network, but only 2.2 million had an active NBN service.
The NBN was designed to deliver a guaranteed minimum connection speed of 25mbps, with all homes and businesses connected by 2020.