The quake's epicentre was roughly 200 kilometres northeast of the Indonesian holiday island and 518 kilometres below the Earth's surface, the European-Mediterranean Seismological Centre said.
It struck just before 3 am.
The Bureau of Meteorology have confirmed there is no tsunami threat to Australia as the earthquake struck deep under the seabed.
Australian tourists woken in the night by earthquake
Scores of Australians visiting Bali said they had felt the "scary" earthquake on Facebook, which one person said lasted for one minute.
"Our whole villa in Ubud was shaking," one person said.
"We were woken from our sleep in Seminyak… now a few people have gone to sit outside," another said.
"Quite a big one," one user wrote, while another said they had experienced quakes in Bali before and this was by far the biggest.
At this stage there are no reports of injuries or damage.
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