The Washington Post, purchased three years ago by Amazon founder Jeff Bezos, will turn a profit in 2016 and expand its newsroom, defying the downward trend in the newspaper industry.

A memo to staff this month from Post publisher Fred Ryan, obtained by AFP, said the newspaper has been helped by its digital efforts and will be launching new "initiatives" in the coming year.

"Thanks to the incredible work of the entire team, the Washington Post will finish this year as a profitable and growing company," Ryan said in the memo.

"In addition to reinforcing our belief that there is a viable business model in quality journalism, this will provide additional funding for several new initiatives that build upon the successes of this year."

The newsroom was "larger this year than last year, and it will grow even more next year," he added.

The newspaper will create a new "rapid-response investigative team" to add to the investigations team, and hire more staff for video, breaking news and other areas.

The Post is likely to add at least 60 positions to boost its newsroom to around 750, as it aims to compete with the New York Times and its staff of 1,300, according to a Politico article by media analyst Ken Doctor.

The paper's growth comes as much of the traditional newspaper industry remains mired in a deep slump as readers migrate to digital platforms and advertising and subscription revenue declines.

Ryan's memo said the Post showed its value during the 2016 election campaign, bringing in more readers online even as it drew fire from the victorious Republican Donald Trump.

"The Washington Post shattered all traffic records over the past year, passing traditional competitors and the largest digital sites," the memo said.

"With monthly unique visitors pushing 100 million in the US alone and 30 million more from around the world, our traffic has increased by nearly 50 percent in the past year, extending the reach of Washington Post journalism to a broader national and global audience."

Subscription revenue has more than doubled in the past year, he added, with a 75 percent increase in new subscribers since January.

The Post has ramped up its technology under Bezos to allow its website to perform better, with improved analytics that gauge how readers are responding and deliver relevant advertising.

It has also made its articles more widely available through social network news services operated by Facebook and Google, and boosted its own social media efforts.

Ryan said earlier this year that the Post was now "a media and technology company" and that Bezos "has given us runway to experiment with new ways to engage with readers and the resources to expand our newsroom and our engineering team."