John Martinkus was seized in Baghdad on Saturday, the first Australian held hostage in Iraq since the US-led invasion.
But his captors agreed to release him after they were convinced he was not working for the CIA or a US contractor.
He was reported to be making his way home to Australia on Tuesday.
His executive producer at Australia’s SBS network, Mike Carey, said Google probably saved freelance journalist Martinkus.
“They Googled him and then went onto a web site – either his own or his book publisher’s web site, I don’t know which one – and saw that he was who he was, and that was instrumental in letting him go, I think, or swinging their decision,” he told AP news agency.
Martinkus told the Australian Broadcasting Corporation that he was snatched at gunpoint from outside a hotel close to Australia’s embassy in Baghdad by Sunni Muslims, and that they had threatened to kill him.
“I told them what I was doing (and that) I wasn’t armed,” he said.
Asked how he coped, he said: “I just kept talking.”