The Bayern Munich striker has previously spoken about his interest in golf and American football, but he now believes becoming an NFL kicker is the more realistic option.
Kane, 33, said he could look at the possibility over the next five or six years.
"That is something I will try and look at a bit more seriously," Kane told reporters at England's training camp. "It all depends on what happens in my career over the next five or six years.
"The NFL is a lot more realistic than the golf one, let's put it that way."
Kane believes there are similarities between taking penalties and kicking in the NFL, particularly when it comes to dealing with pressure and technique.
"I take penalties and it is a very similar pressure and technique," he said. "In terms of training, I would be closer to that more than any other sport."
However, Kane knows switching from elite football to the NFL would require significant preparation.
"If I was to do it, it is something I would take seriously," he said. "I would take maybe six months to a year of trying to practise before."
A spell in Major League Soccer could even help Kane combine the two sports, with the football and NFL seasons taking place at different times.
"Maybe if I am in the MLS in the future or somewhere like that it might be a thing where you could connect the two maybe with the seasons," he said.
Kane would not be the first footballer to make the switch. Dallas Cowboys kicker Brandon Aubrey was a first-round MLS draft pick in 2017, while Detroit Lions kicker Jake Bates played college football before moving into the NFL.
For now, though, Kane's focus remains firmly on football.
The England captain is also close to agreeing a new contract with Bayern, with talks progressing towards an announcement.
"We're in good talks," Kane said. "There's still some things that we need to iron out. I'm happy there. I think it won't be too long before there's some sort of announcement."
Kane's immediate attention will be on England, who face Spain at Wembley Stadium on Saturday in the UEFA Nations League.
Jurgen Klopp was left encouraged by Germany's performance in his first match as head coach, despite seeing his side concede a late equaliser in a 1-1 draw with the Netherlands in the UEFA Nations League on Thursday.
Dani Olmo's agent has welcomed reports of interest from Bayern Munich, but the Barcelona midfielder remains focused on fighting for his place at the Catalan club.
Leeds United star Ethan Ampadu has demanded greater standards from Wales after their winless run was extended by a 1-0 Nations League loss to Portugal in Lisbon.
A brace from Erling Haaland led Norway to a hard-fought victory over Denmark in their UEFA Nations League opener, while Portugal edged out Wales to begin their League A campaign with a win.
