WikiLeaks founder Julian Assange seems to be enjoying his "free" life after being released from a British prison nearly a month ago and returning to his native Australia.

Assange, 53, was released on June 26 from London's Belmarsh prison after a deal was struck to end his 14-year legal struggle with the United States Department of Justice.

Assange's wife, Stella, 40, offered a rare glimpse into her husband's post-prison life, releasing a candid family photo showing the couple basking in freedom on a deserted beach with their two children Gabriel, 7, and Max, 5.

She posted the photo on her Instagram and simply captioned it: "Family photo!".

Earlier, she had also posted a photo on her husband's birthday with the caption: "Free!".

She has previously said he would use his freedom to "swim in the ocean every day".

"He plans to sleep in a real bed. He plans to taste real food. And he plans to enjoy his freedom," she told reporters in Australia shortly after his arrival.

Assange spent over five years in Belmarsh fighting extradition to the US under the 1917 Espionage Act. Before that, he spent seven in Ecuador's London embassy to escape extradition to Sweden over sexual assault charges, which were dropped, AFP reported.

Assange had published hundreds of thousands of confidential US documents on the WikiLeaks whistleblowing website from 2010.

The material he released through WikiLeaks included video showing civilians being killed by fire from a US helicopter gunship in Iraq in 2007.

Assange pled guilty to a single count of revealing military secrets in a US Pacific island court. He was sentenced to time already served and allowed to walk free.