Experts have disputed Facebook chief executive Mark Zuckerberg's claim that less than 1 per cent of the social media network's content is fake, amid accusations hoaxes influenced the United States election outcome.

Mr Zuckerberg said it was "extremely unlikely hoaxes changed the outcome of this election in one direction or the other" in a statement posted on Facebook.

"Of all the content on Facebook, more than 99 per cent of what people see is authentic," Mr Zuckerberg said.

"Only a very small amount is fake news and hoaxes."

But Griffith University's professor of journalism and social media, Mark Pearson, said he was suspicious of the statistic.

"There is an enormous amount of misinformation on Facebook and other social media," Professor Pearson told ABC News.

A Facebook post linking to a fake story on people voting for Harambe in the US election. ( Supplied: Facebook )

During the election campaign, fake news about now President-elect Donald Trump and Democratic presidential candidate Hillary Clinton circulated online.

Stories about Mr Trump calling Republicans the "dumbest group of voters" and Mrs Clinton accidentally paying the Islamic State group $US400 million were among those determined to be false by myth-busting website Snopes.

On election day, stories claiming Harambe the gorilla [who was shot at Cincinnati Zoo earlier this year], received thousands of votes were found to be fake.

"I am sure many of these posts would have influenced voters," Professor Pearson said.

Facebook cautious about being 'arbiters of truth'

University of Queensland journalism and computer science lecturer Dr Daniel Angus said some "trolls" made fake news for fun, but others did it with a political purpose.

This fake quote from Donald Trump was circulated in the lead up to the election. ( Supplied: Facebook )

"Some put it out on the internet as a form of persuasive communication, to try to sway or sow seeds of doubt in people's mind about the character of an individual, or group," Dr Angus said.

"Some can be forms of astroturfing, where the story is constructed by lobby groups or other professional or political organisations, to try to attempt to discredit someone."

Mr Zuckerberg said Facebook has tools to help stop hoaxes.

"We have already launched work enabling our community to flag hoaxes and fake news," he said.

But Mr Zuckerberg said identifying what is true is "complicated".

"While some hoaxes can be completely debunked, a greater amount of content, including from mainstream sources, often gets the basic idea right but some details wrong or omitted," he stated.

"An even greater volume of stories express an opinion that many will disagree with and flag as incorrect even when factual.

"I am confident we can find ways for our community to tell us what content is most meaningful, but I believe we must be extremely cautious about becoming arbiters of truth ourselves."

Be critical

"Many social media users have difficulty distinguishing between fake and real news because social media literacy is still building, Professor Pearson said.

But fake news is not restricted to Facebook — Dr Angus said it was "all over the internet".

He said there were several ways people can tell the difference between fake and real news.

"Obvious sensational titles are one giveaway," he said.

"Also look at the quality of the hosting organisation, and also if this is something that many different credible news sources have commented on.

"Also there are sites such as snopes.com which have a database of known/debunked fake stories that is regularly updated.

"Essentially, be critical when you read online content."