Geonet says it was at a depth of 146 kilometres, north west of French Pass at the top of the South Island.
More than 13-thousand people from as far south as Christchurch and north to Auckland have reported feeling the shake, most saying it was light to moderate.
Linda told Newstalk ZB it happened during the 3am news bulletin.
She says it felt like quite a good shake, and gave her wardrobe door a good rattle.
There have so far been no reports of damage.