The Australian, who won two golds and two silver medals at the Paris Olympics, said she may spend up to a year away from the sport as she looks to recharge her batteries.
"I'm definitely having a very extended break. I haven't planned when I'm going back to swimming. I want to go back when I feel ready to go back. Could be up to 12 months," she told news agency reporters on Monday.
Titmus, who won gold in the 400 metres freestyle and the 4x200m freestyle relay in Paris, along with silver in the 200m and 800m freestyle, will turn 24 next month and is keen to be fresh and ready in four years time.
"I just want to make sure I'm ready to go in LA. I don't want to come back too early and, you know, lose that fire, I guess," she said.
"I think four years is a long time, so I want to prepare myself the best for those Olympic Games. For me, that's the priority, not world championships in the years prior.
"So I just want to really have time to let the hunger build back up and enjoy myself for a little while," she said.
Titmus' great rival, American Katie Ledecky, has said she aims to continue on for a fifth Olympics which would set up another series of their contests.
While Titmus has beaten Ledecky to gold in the past two Olympic 400m events, the American, who is 27, has won four straight golds in the 800m.
The Tasmanian said she was glad their duel looked to set to resume.
"t's always exciting racing the best in the world and I think we get the best out of each other," she said.
"You know, it's more satisfying racing a champion like her and being successful than not. So I think it'd be crazy for her not to try and keep going for her home games.
"And yes, it's another challenge, it is always a challenge racing her so I look forward to it," she added.
With Canadian teenager Summer McIntosh having emerged as a major star, with two golds in Paris, Titmus feels women's swimming is in a golden era.
"I think that at the moment, it's probably, since I can remember, the best it's ever been in terms of how fast we're swimming, the depth we have across the world, the depth in Australia," she said.
"So I feel very privileged and have a sense of pride to contribute to that at the moment. I think people are going to look back on this era of swimming and say that it was one of the best."
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