Rumors have sparked that that the Avengers: Infinity Wars, Part 1 and 2 will have a $1 billion budget between the two movies. If this is the case, then these third and fourth installments of the Avengers series will be the most expensive movies of all time.

Making a movie is an expensive process - in addition to paying for sets, equipment, props, and special effects that appear on camera, budgets need to pay for actors, technicians, designers, and other staff. After the movie has been filmed, the editing process and special effects must also be taken into account. The film industry is a massive business, and movie budgets have only continued to increase in recent years.

For this list, we chose to rank films based on the estimated dollar amount. While many films do not publish their exact budget, there is a general consensus based on interviews and reports about how much was spent on a film. Because of this, any number that has not been officially verified features a "~" before the number. We decided to not take inflation into account - so Titanic does not make the list, because it cost approximately $200 million dollars to make in 1997. However, after adjusting for inflation, Titanic would likely fall on the list as the second most expensive movie of all time.

However, inflation does not change the list as much as one might think. Other than adding Titanic and Waterworld (1995) to the list, there are no other movies added from before the 2000s. In the past twenty years, movie budgets have increased at an alarming rate as filmmakers and producers invest more money into their productions.

Each of the films on this list have budgets that are greater than the upcoming The Hunger Games: Mockingjay - Part 2 or Star Wars Episode VII: The Force Unleashed. Here are the 10 Most Expensive Movies Ever Made:

10. Avatar (2009)

Cost: $237 million

Avatar turned out to be less expensive than audiences believed. Initially, reporters speculated that the luscious visual film could cost anywhere between $280 million and $500 million. However, Fox officially released the production cost, revealing that the film had a (relatively measly) $237 million budget.

Avatar pioneered film technology and motion capture animation. Cameron's team developed the technology and software for the film's motion capture in the 14 months leading up to filming. He also employed over 900 people at Weta Digital to work on the film's digital after-effects. The technology developed and used was necessary to make Cameron's vision a reality.

Avatar was the first film to make over $2 billion dollars worldwide, and it remains today the highest grossing film of all time (or at least until Star Wars: The Force Awakens arrives).

9. The Hobbit: An Unexpected Journey (2012) / The Hobbit: The Desolation of Smaug (2013) / The Hobbit: The Battle of Five Armies (2014)

Cost: ~$248.3 million (each; $207 million each after tax rebate)

The Hobbit trilogy cost a total of $745 million to create - while some film experts divide the the prices of the films unevenly, speculating that the third installment, The Hobbit: The Battle of Five Armies (2014), cost more. However, the three films were created simultaneously, and dividing the costs between the two films is difficult. Even when the cost is divided evenly, all of the Hobbit films would appear on the top ten most expensive list. The cost of the films are often attributed to the fact that they were filmed both in 3D and in 45 frames per second.

This figure can be compared to the price of the original Lord of the Rings movie trilogy, which was made for $281 million. The Hobbit trilogy made $2.932 billion dollars at the box office, in comparison to the Lord of the Rings' $2.917 billion dollars worldwide.

7.  Pirates of the Caribbean: Dead Man’s Chest (2006) / Pirates of the Caribbean: At World’s End (2007) (tie)

Cost: ~$250 million (each)

The second and third Pirates of the Caribbean movies were filmed in tandem. However, even when filmed together, they cost Disney $500 million dollars. Even when the cost is split evenly between the two films (as it is difficult to allocate which funds were spent on which film, given that they were shot simultaneously and many of their expenses, including actor's salaries, were combined costs), they would still both appear in the list of the most expensive movies ever made.

Like the fourth installment of Pirates of the Caribbean, a combination of A-list actors - including Johnny Depp, Orlando Bloom, and Keira Knightley - exotic locations, and special effects led to an increase in production costs. Ironically, the large budget of the second and third Pirates of the Caribbean movies prompted discussions of how the fourth film could be made cheaply and efficiently.

7. Harry Potter and the Half-Blood Prince (2009) (tie)

Cost: ~$250 million

The sixth installment of the eight Harry Potter movie series, Harry Potter and the Half-Blood Prince had the largest budget of any single Harry Potter film. It is likely that the final installment of the Harry Potter series, Harry Potter and the Deathly Hallows would have had a similarly enormous budget (of approximately $250 million), but it was split into two separate films that were filmed simultaneously on the same budget, cutting the production costs of each film significantly. The film brought back stars Daniel Radcliffe as Harry Potter, Rupert Grint as Ron Weasley, and Emma Watson as Hermione Granger. Additionally, famed actors Maggie Smith, Ralph Fiennes, and Alan Rickman appear as Prof. McGonagall, Lord Voldemort, and Prof. Snape respectively.

The film grossed almost a billion dollars ($934.4 million). Harry Potter continues to be a cultural phenomenon, with a new movie based loosely on the book Fantastic Beasts and Where to Find Them will be released in November 2016.

6. The Amazing Spider-Man 2 (2014)

Cost: ~$255 million

The Amazing Spider-Man 2 is the sequel to Andrew Garfield's first film as Spider-Man. Almost $500 million dollars went into rebooting the series, which also starred Emma Stone as Gwen Stacy. The second film also starred Jamie Foxx as Electro, whose obsession with Spider-Man takes a dangerous turn. Filmed exclusively on 35mm film, it was filmed entirely in New York state, with many sequences shot in New York City. Governor Cuomo described the production as the largest movie production shot entirely in New York.

While The Amazing Spider-Man 2 performed well at the box offices, its sequels were postponed and eventually canceled because Sony Pictures chose to partner with Marvel Studios and include Spider-Man in upcoming films. Instead of continuing with Andrew Garfield, Sony chose to recast Spider-Man with Tom Holland, who will appear as Parker in the third Captain America movie, Civil War.

5. Spider-Man 3 (2007)

Cost: $258 million

The budget of Spider-Man 3 was verified when Sony publicly acknowledged the production cost to be $258 million. Helmed by director Sam Raimi, the third installment of the Tobey Maguire Spider-Man trilogy was filmed in Los Angeles, Cleveland, and Peter Parker's hometown, New York City. In the film, Spider-Man faces off with three different adversaries: Sandman (Thomas Haden Church), Venom (Topher Grace), and Harry Osborn as New Goblin (James Franco).

Grossing $890.9 million, Spider-Man 3 was the most financially successful of the trilogy, even if it was met with a mixed critical reception. While a fourth film was considered, Sony and Raimi had a falling out. Instead, Sony eventually decided to reboot the franchise only five years later with Andrew Garfield as Spider-Man.

4. Tangled (2010)

Cost: ~$260 million

Tangled is a Disney musical comedy that utilizes 3D animation. Loosely based on a story by the Brothers Grimm, it features Rapunzel, the first official Disney princess to be rendered in 3D rather than 2D. Tangled is the most expensive animated film of all time, with many film experts estimating that it cost approximately $260 million. The cost is usually attributed to the the fact the film was in production for six years, during which time the production team developed state of the art programs to code how Rapunzel's hair should move and behave in water.

Tangled performed well for an animated film at the box office, making $591.8 million worldwide. Generally well-received by critics, it also was nominated for two Golden Globes, an Oscar, and won a Grammy for its song "I See the Light."

3. John Carter (2012)

Cost: $306.6 million ($263.7 million after tax rebate)

Based on Edgar Rice Burroughs' seminal sci-fi classic A Princess of Mars, John Carter was a science fiction movie set on Mars that starred Taylor Kitsch.

John Carter's budget became one of the the reasons that it was a box office flop. The film made only $284.1 million, which did not make up for the cost of the film's production and marketing. Filming took longer than expected, with many scenes being completely reshot. Additionally, more than 2,000 visual effects were added post-production. The film was shot in the United States and the United Kingdom, and the tax rebate from the United Kingdom revealed the cost of the film to be over $300 million.

While a sequel was discussed, it was put on hold after John Carter's lackluster performance in theaters, especially at the domestic (U.S.) box office. But John Carter's massive budget created an environment where it would only really have been a success if it performed as well as the highest grossing 100 movies of all time.

2. Avengers: Age of Ultron (2015)

Cost: $330.6 million ($279.9 million after tax rebate)

The sequel to Joss Whedon's successful first Avengers movie, Avengers: Age of Ultron features an all-star cast, including Robert Downey, Jr. as Iron Man, Scarlett Johansson as Black Widow, and Chris Evans as Captain America. The film was shot primarily in England, with on-site filming in Bangladesh, Italy, New York City, and South Korea. The tax rebate from the United Kingdom verified the cost of the film to be $330.6 million. An international movie with a large cast, even before considering the cost of post-production special effects, the second Avengers movie would be a very expensive movie.

Avengers: Age of Ultron went on to make $1.403 billion dollars at the box office, making it the sixth-highest grossing film of all time. It did not, however, outperform the first Avengers movie, which sits at the fourth-highest grossing film of all time. The upcoming sequels, Infinity Wars Part 1 and Part 2, have the potential to be even more expensive.

1. Pirates of the Caribbean: On Stranger Tides (2011)

Cost: $410.6 million ($378.5 million after tax rebate)

Pirate of the Caribbean: On Stranger Tides (2011) is the first and only individual film to cost more than $400 million. The fourth installment of the Pirates of the Caribbean series, it stars A-list actors Johnny Depp and Penelope Cruz as Captain Jack Sparrow and Angelica, two buccaneers in search of the Fountain of Youth.

The film was shot in the United Kingdom and in Hawaii. It utilized similar 3D film technology that was used for James Cameron's Avatar, and featured around 1,200 computer generated sequences. When producers filed for a tax rebate in the United Kingdom, it was revealed that the production costs had totaled $410.6 million, making On Stranger Tides definitively and without question the most expensive movie of all time.

The investment appears to be worthwhile, as it made over a billion dollars ($1.046 billion) at the box office.

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Which of these movies deserved their budget, and which ones were a waste? Tell us in the comments!