Thousands gathered on San Francisco's Ocean Beach to see the 39-year-old American add to his legend by clinching the 2011 crown on Wednesday with a third round victory at the penultimate event, the Rip Curl Search.
It gave him an unassailable lead over his nearest rival, Australian young gun Owen Wright.
"I've dedicated my whole life to surfing and to competing so, to go a whole year and to win a world title and have it all pay off for all that work and effort, it's a really rewarding feeling," said Slater.
Since the ASP World Tour rankings began in 1976, no one has dominated men's surfing like Slater.
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While Australia's Layne Beachley has come the closest with seven world titles to her name, her compatriot Mark Richards with four remains second on the men's list.
This year he has won three world tour events and reached four of the past five finals.
He shows no sign of departing the scene anytime soon.
"People always talk about my age. I'm 39 going on 40 in a few months and, to me, that's literally just a number," Slater said.
"If you can prove people wrong and stay healthy... to me, I don't see why at 50 I can't be in better shape than right now, and I think I'm going to be."
Securing the title at this event was bittersweet for Slater, coming a year to the day since great rival and friend Andy Irons was found dead in a hotel room.
"It's like someone's looking over us here - it's probably Andy.
"It's sort of weird. I was thinking what's the chances I do this on the anniversary of unfortunately Andy passing away.
"In a way, it makes it a lot more special for me than any other world title."
While Wright has lost out to Slater this year, he feels his time will come and he believes it's possible someone among the current crop of young stars could even challenge Slater's achievement.
"You only have to look at the younger generation coming through now, like Julian (Wilson), myself, Gabriel (Medina)," said Wright.
"Those guys all have the potential to be on the tour for more than another 10 years and the potential to win world titles.
"Kelly's been doing 20 years now and 11 is a big feat. I don't know if anyone's ever going to match it but there are definitely guys out there who have the potential to."
Slater wasn't surprised by Wright's emergence as his main threat this year.
"Aussies are just competitive by nature. There's so many surfers, so it never surprises me when I have someone like Owen challenging for the title," he said.
"The level of surfing there is pretty remarkable."
Slater's title clinching heat wasn't an easy one as he scored 15.13 in the four-foot swell to narrowly beat Australia's Dan Ross (14.40).
He took until the final two minutes to secure the victory, needing a score of 6.88 from his last wave and scoring 7.6.
"I've been pretty stressed about it to be honest," he admitted.
"I'm just glad it's over."
