A film adaptation of Eragon was released in the United States on December 15, 2006. Plans to create the film were first announced in February 2004, when 20th Century Fox purchased the rights to Eragon. The film was directed by first-timer Stefen Fangmeier, and written by Peter Buchman. Edward Speleers was selected for the role of Eragon. Over the following months, Jeremy Irons, John Malkovich, Chris Egan and Djimon Hounsou were all confirmed as joining the cast. Principal photography for the film took place in Hungary and Slovakia.
The film received mostly negative reviews, garnering a 16% approval rating at Rotten Tomatoes; the tenth worst of 2006. The Seattle Times described it as "technically accomplished, but fairly lifeless and at times a bit silly". The Hollywood Reporter said the world of Eragon was "without much texture or depth". The story was labelled "derivative" by The Washington Post, and "generic" by the Las Vegas Weekly. Newsday stressed this point further, asserting that only "nine-year-olds with no knowledge whatsoever of any of the six Star Wars movies" would find the film original. The acting was called "lame" by the Washington Post, as well as "stilted" and "lifeless" by the Orlando Weekly. The dialogue was also criticized: MSNBC labelled it "silly"; the Las Vegas Weekly called it "wooden". Positive reviews described the film as "fun" and "the stuff boys' fantasies are made of". The CGI work was called "imaginative" and Saphira was called a "magnificent creation". Paolini stated he enjoyed the film, particularly praising the performances of Jeremy Irons and Ed Speleers.
Eragon grossed approximately $75 million in the United States and $173.9 million elsewhere, totaling $249 million worldwide. Eragon is the thirteenth highest grossing fantasy-live action film within the United States; twenty-first when adjusted for inflation. It is the second highest grossing film with a dragon at its focal point, and the sixth highest grossing film of the sword and sorcery subgenre. Eragon was in release for seventeen weeks in the United States, opening on December 15, 2006 and closing on April 9, 2007. It opened in 3,020 theaters, earning $8.7 million on opening day and $23.2 million across opening weekend, ranking second behind The Pursuit of Happyness. Eragon’s $75 million total United States gross was the thirty-first highest for 2006. The film earned $150 million in its opening weekend across 76 overseas markets, making it the #1 film worldwide. The film’s $249 million total worldwide gross was the sixteenth highest for 2006.