CNN reports that it is Disney's 17th film to reach the billion dollar mark.
The previous record of fastest time for a movie to make a US$1 billion was 12 days for Star Wars: The Force Awakens.
Avengers has surpassed other hits like Guardians Of The Galaxy, Wonder Woman, Justice League, X-Men: Days Of Future Past and Batman V Superman: Dawn Of Justice in just 11 days since its release.
The star-stuffed Infinity War features Robert Downey jnr, Benedict Cumberbatch, Scarlett Johansson, Elizabeth Olsen, Zoe Saldana, Josh Brolin, Chris Pratt and Mark Ruffalo.
The film has made most of its money, US$605m so far, in the international marketplace.
But it has yet to open in China. AIW will be released in China, the second biggest movie market in the world, on May 11.
It is the sequel to 2012's The Avengers and 2015's Avengers: Age of Ultron, and the 19th film in the Marvel Cinematic Universe.
The movie is directed by Anthony and Joe Russo, written by Christopher Markus and Stephen McFeely.
In Avengers: Infinity War, the Avengers and Guardians Of The Galaxy attempt to stop Thanos from collecting the Infinity Stones.
Having acquired the Power Stone from the planet Xandar, Thanos and his lieutenants— Ebony Maw, Cull Obsidian, Proxima Midnight, and Corvus Glaive — intercept the spaceship carrying the survivors of Asgard's destruction.
They extract the Space Stone from the Tesseract, as Thor is subdued, and Thanos overpowers Hulk and kills Loki. Heimdall sends Hulk to Earth using the Bifröst before being killed. Thanos departs with his lieutenants and obliterates the ship.
The film was announced in October 2014 as Avengers: Infinity War – Part 1. In 2016, Marvel shortened the title. Filming began in January 2017 at Pinewood Atlanta Studios in Fayette County, Georgia, and lasted until July 2017, shooting back-to-back with a direct sequel.
Infinity War is Marvel's sixth film to hit a billion and Disney's 17th.
