The shaking was strong enough to topple televisions and other appliances in Wellington and other communities late Tuesday evening, but there were no reports of significant damage or injuries.
While the GNS Science agency in New Zealand placed the magnitude at 7.0, the U.S. Geological Survey said it was a more modest 6.2.
New Zealand seismologist Lara Bland told reporters the quake was the largest beneath the South Taranaki Bight since a magnitude 7.2 temblor struck there in 1893.
Earthquakes are common along the entire length of New Zealand.
A 6.3-magnitude quake killed 185 people in the country’s second largest city of Christchurch in February 2011 as it flattened office blocks and toppled buildings onto lunchtime crowds.