Kate Winslet broke Hollywood records while filming “Avatar: The Way of Water” — and thought she died while doing it.

The 47-year-old actress deprived herself of air for all of seven minutes and 15 seconds, beating actor Tom Cruise’s best time of six minutes while on the set of “Mission: Impossible — Rogue Nation” in 2011.

“I have the video of me surfacing saying, ‘Am I dead, have I died?’ And then going, ‘What was [my time]?’” the actress told Total Film magazine via Games Radar, alongside her director, James Cameron.

Winslet noted how quickly she got over the shock of her near-death experience.

“Straight away I wanted to know my time. And I couldn’t believe it … The next thing I say is, ‘We need to radio set.’ I wanted Jim to know right away,” she shared.

Joked her “Titanic” collaborator: “She’s not competitive at all.”

“Well, I didn’t have to hold my breath for over seven minutes,” Winslet assured. “It’s just that the opportunity to set a record presented itself. I wanted to break my own record, which was already six minutes and 14 seconds. And I was like, ‘Come on!’ So I smashed my own record by a minute.”

Cameron had wanted to limit the “dry for wet” ocean scenes and make the water sequences feel real and authentic — which meant having the actors act underwater.

“I said, ‘It’s not going to work. It’s not going to look real,’” the 68-year-old filmmaker explained. “I even let them run a test, where we captured dry for wet, and then we captured in water, a crude level of our in-water capture. And it wasn’t even close.”

Winslet portrays Ronal, leader of the Metkayina — a lesser-known clan of the Na’vi tribe — in the highly anticipated sequel to the 2009 blockbuster.

The upcoming installment picks up a decade from where the original left off, with the story of the Sully family as they fight for their home on the lush alien planet of Pandora.

“Avatar: The Way of Water” premiers in theaters nationwide on Dec. 18.