Question: what is the most selling movie of all time

title: List of highest-grossing films
text: With a worldwide box - office gross of over $2.7 billion , Avatar is often proclaimed to be the `` highest - grossing '' film , but such claims usually refer to theatrical revenues only and do not take into account home video and television income , which can form a significant portion of a film 's earnings . Once revenue from home entertainment is factored in it is not immediately clear which film is the most successful . Titanic earned $1.2 billion from video and DVD sales and rentals , in addition to the $2.2 billion it grossed in theaters . While complete sales data are not available for Avatar , it earned $345 million from the sale of sixteen million DVD and Blu - ray units in North America , and ultimately sold a total of thirty million DVD and Blu - ray units worldwide . After home video income is accounted for , both films have earned over $3 billion . Television broadcast rights will also substantially add to a film 's earnings , with a film often earning as much as 20 -- 25 % of its theatrical box - office for a couple of television runs on top of pay - per - view revenues ; Titanic earned a further $55 million from the NBC and HBO broadcast rights , equating to about 9 % of its North American gross . 

Answer: answer: With a worldwide box - office gross of over $2.7 billion , Avatar is often proclaimed to be the `` highest - grossing '' film , but such claims usually refer to theatrical revenues only and do not take into account home video and television income , which can form a significant portion of a film 's earnings . After home video income is accounted for , both films (Titanic and Avatar) have earned over $3 billion .