A magnitude 6.1 earthquake has struck off the Kāpiti Coast, Geonet says.

The quake struck at 7.38pm 50km north-west of Paraparaumu at a depth of 48km, with strong shaking, says Geonet's report on the quake.

Within 10 minutes, more than 28,000 people reported feeling the quake, with most reporting shaking ranging from weak to moderate.

However, more thousands of people reported shaking ranging from strong to extreme.

People as far away as Southland and Northland reported feeling the quake.

RNZ staff in Wellington said the office was hit by a "solid and long rumble that went on for a fair bit. Nothing knocked over though" and "a good shake that lasted a surprisingly long time".

- RNZ.