The defending champion, 36, insists his rivals have a better chance than him in the first Grand Slam of 2018.
Federer picked up the Australian Open title last year in his first Slam success in five years.
And it set up a stunning year where he also claimed the Wimbledon title and finished the year as world No 2.
But he thinks Nadal, who finished the year as world No 1, and Djokovic, who has six Australian Open victories, could win it this year.
“It’s totally different,” he said.
“This year I hope to win the first few rounds and get rolling hopefully, whereas last year I was just hoping to win (a match). It was more of a ‘let’s see what happens’ kind of tournament, maybe similar to what Novak or Stan (Wawrinka) or others are going through this year.
“If you’re in the draw, you give yourself a chance. That’s what happened for me last year. And it ended up way better than I thought it would.
“It was the tournament of the year for me, no doubt about it. Having no expectations was so nice after all these years always having expectations, like now this year again.
“With age I feel like I play down my chances just because I don’t think a 36-year-old should be a favourite of a tournament.
“I feel like maybe somebody like a Rafa, with the year that he’s had, and Novak, with the six titles he’s had here, even if it’s unknown how he’s feeling, they could very well be the favourites, too.
“It’s just great to be back. I’m so, so happy the Australian Open, it’s time again. I can’t believe it’s been a year, but it’s okay. I’ll make the most of it.”