LOS ANGELES — James Cameron’s science-fiction epic “Avatar” has passed his “Titanic” to become history’s highest-grossing film, with a sizable boost from higher-priced tickets for 3-D and Imax showings.

“Avatar,” like other contemporary films, has also benefited from the steady inflation of ticket prices —today’s average is $7.46, up from $4.69 in 1998 when “Titanic” was in theaters — meaning that “Titanic” had to sell many more tickets to reach box-office totals like “Avatar’s.” But “Avatar” remains poised to keep going for weeks if not months.

Through Monday its ticket sales around the world reached $1.86 billion, edging past the $1.84 billion in sales posted by “Titanic,” which came out in December 1997, according to figures released Tuesday by 20th Century Fox.

Fox released “Avatar” around the world; it split the distribution of “Titanic” with Paramount Pictures.

Through Monday “Avatar” took in about $554.9 million in domestic theaters, placing it just behind “Titanic,” with sales of $600.8 million, in the domestic box-office rankings, and just ahead of “The Dark Knight,” a Warner Brothers film from 2008, which took in $533.3 million.

The performance of “Avatar” is particularly striking because the film — a leading contender in this year’s Oscar race — reached its summit so quickly.
“In just 39 days it has eclipsed the worldwide record,” said Paul Dergarabedian, the president of Hollywood.com’s box-office division. “That’s extraordinarily impressive.”

Mr. Dergarabedian said he thought “Avatar” would pass the domestic box-office mark set by “Titanic” by the middle of next week, and that it is almost certain to pass $2 billion in worldwide sales before the end of its run.

Privately, some involved with the film are guessing that final ticket sales will go as high as $2.5 billion, though Fox has made no public projection. New Line Cinema’s “Lord of the Rings: The Return of the King,” No. 3 in the all-time worldwide rankings, had $1.1 billion in ticket sales, according to Boxofficemojo.com.

Fox said 72 percent of worldwide sales for “Avatar” came from 3-D screens. If Mr. Dergarabedian’s estimates are correct, the movie has accounted for roughly 56 million admissions in domestic theaters to date.
That is about the same number of tickets that “Titanic” had sold at this point in its theatrical run, he said.

But “Titanic” played and played, remaining in theaters until September 1998 and racking up about 128 million admissions. “Avatar” still needs a very long tail to surpass the number of viewers who saw “Titanic.”

To calculate the number of “Avatar” viewers around the world is impossible without taking into account exchange rates and a patchwork of ticket prices and viewing habits in dozens of countries in which the film has been showing.

Large-format Imax theaters have accounted for about $137.1 million of “Avatar” ticket sales around the world, said Greg Foster, president and chairman of Imax Filmed Entertainment. “There’s been only the most minimal drop-off,” he said. Imax theaters are scheduled to continue showing “Avatar” until “Alice in Wonderland,” another 3-D film, from Walt Disney, opens on March 5.

The world record is sweet vindication, both for Mr. Cameron and for Fox. Skeptics had questioned whether Mr. Cameron could deliver on his promise of a revolutionary visual experience, and whether Fox and its financial partners would profit from a film that cost nearly a half-billion dollars to make and release.

While those questions are now settled — the film will make a profit and the critics have been kind — the Academy Awards, scheduled for March 7, remain a hurdle. On Sunday the Producers Guild of America gave its highest movie award, sometimes a harbinger of success at the Oscars, to “The Hurt Locker.” A small, independent drama about the Iraq war, it was directed by Kathryn Bigelow, who is Mr. Cameron’s ex-wife.

On Tuesday Tom Rothman, a chairman of the Fox film operation, said the global success of “Avatar” carried a lesson beyond economics. “It tells you all of us on the planet have more things in common than we have dividing us,” Mr. Rothman said.