Iron Man 3 starts rolling out to U.S. theaters at midnight tonight, but it has already surpassed $300 million at the international box office – crushing previous records.

U.S. Marvel fans are just getting ready for their Iron Man 3 midnight premieres, meanwhile the film has been overseas smashing box office records. Marvel’s first summer film easily passed the $17 million that Transformers: Dark Side of the Moon raked in, which has held the record for biggest opening day in China until now. Iron Man 3 pulled in $21.5 million on it’s opening day, and then went on to take in $65 million this past Wednesday, which pushed the total to a reported $307.7 million.

Iron Man 3 also broke the record for biggest midnight premiere in China, most likely due to the fact that the film was co-produced by the chinese based production company DMG. So far the film has already passed the entire international box office numbers for the first Iron Man film ($267 million), Thor ($268 million), and Captain America: The First Avenger ($192 million) – and it’s only been out for less than 10 days.

It has yet to pass Iron Man 2’s numbers, which come in at $311.5 million internationally, but is expected to go on and surpass that before the day is over. Iron Man 2 went on to bring in a total of $623 million worldwide, which could be doubled by Iron Man 3 if the numbers hold strong. Although, the film has been slipping a bit on review aggregate Rotten Tomatoes with an 80%, but the user reviews remain strong at 99%.

According to THR, Korea leads the box office so far with $27.6 million, but Mexico and the U.K. are within a few hundred thousand. It’s fairly impressive to see the film pass $300 million within its first week in foreign markets, which means we may be looking at Avengers type box office numbers by the time it leaves theaters.

It’s currently tracking for a $160 million opening weekend here in the U.S., and if the international numbers are anything to go by, it may even surpass that. For reference, The Avengers pulled in $207 million during its opening weekend in the U.S. and ended up with a domestic total of $623 million, and $888 million internationally. Once again this proves that international markets have become more and more vital to the success of blockbusters and we imagine with Iron Man 3 being marketed by Disney this time has helped tremendously.

Hypable was at the U.S. press conference earlier this week, so be sure to check out the Q&A with Robert Downey Jr., Gwyneth Paltrow, Sir Ben Kingsley, and Don Cheadle.

Earlier this month it was announced by Fandango that according to a survey it performed, Iron Man 3 is the most anticipated movie of the summer. We look forward to seeing our readers’ reactions as they see the film in the next few days.