The triumph earned Gilmore $13,250 and a $28,000 bonus as the best surfer across the three World Tour events in Hawaii.

"I feel like I've got nothing left to prove really and I'm just working on my own performance in the water," Gilmore said.

"If the titles and all the awards keep coming with it, I'll gladly take them.

"I'm just stoked to be travelling the world and competing and enjoying it."

Gilmore easily won the decider, but Fitzgibbons pushed her all the way in the semi-final.

The Queenslander scored rides of 7.63 and 8.40 to finish with 16.03, just 1.09 ahead of Fitzgibbons, who scored 7.17 and 7.77 for a total of 14.94.

Fitzgibbons secured a showdown with Gilmore via a quarter-final triumph over fellow tour newcomer Coco Ho earlier in the day.

"I always love surfing heats with Coco," Fitzgibbons said.

"She always pushes my level up and I usually have my best heats with her.

"She's also a really great friend.

"I wish there were more waves so we could have duelled a little bit more.

"She has surfed amazingly this year and my hat goes off to her."

Gilmore sealed her third World Championship in as many seasons with a tour stop to spare.

Brazil's Silvana Lima finished second and Mulanovich third.

Ho, from Hawaii, and 2008 World Qualifying Series champion Fitzgibbons rounded out the top five.