Even residents who are well used to the regular earthquakes that have followed ever since the large 7.1 quake in September 2010 reported feeling a little frazzled.
Christchurch resident Leony Miller was sitting on her bed when the earthquake hit.
"Everything moved, it was strong, it was really strong...it felt like a five."
Another resident, Barbara, told Newstalk ZB her dogs alerted her to the shake.
"The dogs over the back were barking their heads off, and then it all started to shake."
Many others took to social media to share their experience.
One reader said the quake had shattered her children's nerves once again.
"If this is earth, what is hell like?"
Another said it sent "Christchurch flying", while another speculated whether it was time to leave the city.
"I genuinely thought my house was going to fall down on top of me. Get me out of Christchurch."
But despite the hefty tremor, the latest shake wasn't as big as the one felt in February this year, when Christchurch was rocked by a 5.7 quake - the largest in four years.
The February tremor sent cliff faces crumbling into the ocean, knocked items of shelves and caused liquefaction to bubble up from the earth. It struck just eight days out from the five-year anniversary of the February 22, 2011 quake which killed 185 people.
However, this time around there appeared to be little damage done to the city.
General manager at The Bog in Christchurch, Jesse Crowe, said the quake hadn't dampened the spirits of the pub goers and nothing had fallen off the shelves.
"It was only a weak one. Everyone just cheered [when it happened]."
Emergency services reported no calls had been received related to the quake.
However, a St John's spokesman said it was a timely reminder of how important it was to always be prepared.
"As this earthquake shows, Canterbury is still an active earthquake area."
He encouraged people to check on loved ones, "especially those who are alone, or ill and who may need support."
The spokesman said people should also check their emergency kits and supplies.
A Christchurch city council media spokeswoman said the mayor was unable to comment this evening but did say the earthquake was a "good shake".
The earthquake's epicentre was located just a few kilometres away from the 6.3 quake that caused the deaths of 185 people on February 22, 2011.
GNS Science duty seismologist Caroline Little said there had been many other earthquakes centred around tonight's quake location.
The quake was another one of thousands - and 1250 in the last year alone - that had followed the 7.1 earthquake that struck at Darfield on September 4, 2010.
That event triggered activity on a web of faults beneath the region that would likely carry on for years to come.
Ms Little said that, as recently as late March, the probability of a magnitude 5.7 quake striking was 57 per cent.
"So it's not unexpected to have something in the magnitude 4 range."
She expected the quake to be followed by a series of smaller shakes, perhaps measuring magnitude 3.
It was too early to describe the dynamics of the earthquake - or the faulting mechanism that caused it - and scientists would be investigating this along with its ground acceleration rate tomorrow.
In the past year, Geonet seismometers have picked up 15 quakes in Canterbury measuring between magnitude 4 and 5, along with three between magnitude 5 and 6, 88 between magnitude 3 and 4 and 1144 under magnitude 3.
