Almost 80 years after first going to print, the final Newsweek magazine hit newsstands on Monday featuring an ironic hashtag as a symbol of its Twitter-era transition to an all-digital format.

The second-largest weekly news magazine in the United States has been grappling with a steep drop in print advertising revenue, steadily declining circulation and the migration of readers to free news online.

The final print edition of Newsweek is seen in Washington. Newsweek ends 80-year run as a weekly news magazine with a final print edition published this week and dated Dec 31, 2012. Karen Bleier / Agence France-Presse

During a fierce decades-long rivalry with fellow US coffee-table staple Time magazine, Newsweek pushed the envelope with bold and often controversial covers.

Its first issue, on Feb 17, 1933, featured seven photos from that week's news printed on the front, including Adolf Hitler snapped in Berlin as he declared: "The German nation must be built up from the ground anew."

For its final cover, dated Dec 31, editor Tina Brown used an aerial archive shot of the magazine's New York headquarters as the backdrop for her message - #LASTPRINTISSUE - the word "print" emblazoned in red ink.

"The issue in your hand is the last edition of Newsweek in print," wrote Brown in an introduction titled: "A new chapter: Sometimes, change isn't just good, it's necessary."

"The next (issue), in the first week of January, will be on your iPad or Kindle or phone. By late February, you will see the full evolution of the spanking-new, all-digital Newsweek Global, currently in development."

The Washington Post sold Newsweek to California billionaire Sidney Harman for $1 in 2010, ahead of a deal with Internet conglomerate IAC to merge the magazine with the news and opinion website The Daily Beast.

Memorable Newsweek covers in recent years have included a December 2003 edition with a bedraggled, long-bearded Saddam Hussein pictured beneath the headline: "We got him."