People in Tonga are reporting only minor damage, while the earthquake was widely felt in Fiji, but there are no reports of damage.
The epicentre was 270km east of Levuka in Fiji and 443km west of Neiafu in Tonga and hit just before 1pm.
It didn't trigger a tsunami as it was too deep at 580 kilometres.
Ta Lita Kefu from Nukuʻalofa said she was outside when the earthquake began.
