Ralph Breaks the Internet is rated PG for some action and rude humor.
According to Common Sense Media, the film is recommended for ages 8 and up. 
Common Sense Media states: “Parents need to know that Ralph Breaks the Internet -- the sequel to Disney's hit video-game comedy Wreck-It Ralph -- tells a strong friendship story within its framework of video game characters, popular websites, and social media platforms. It will appeal to viewers of all ages, but the themes and messages (particularly those about the nature of online life and internet fame) are best suited to tweens and up. Several scenes take place inside a Grand Theft Auto-esque driving game called Slaughter Race that's full of weapons, creepy clowns, and lots of danger, stunts, and crashes. Other scary moments/characters include a creepy dark web kingpin and an out-of-control insecurity virus that turns into a giant monster and threatens everything in its path, including Ralph (voiced by John C. Reilly) and Vanellope (Sarah Silverman). Expect some potty humor/language ("butt," "doody") and insults ("stink brain," "dummy," "stupid," etc.), as well as a ton of featured tech logos and brands, from eBay and Google to Facebook, Instagram, and Twitter. Parent company Disney also has a big presence, specifically the Disney princesses, who play a role in the story. The movie fully explores how the internet can be both wonderful and terrible and has strong themes of empathy, courage, perseverance, and self-control.” (https://www.commonsensemedia.org/movie-reviews/ralph-breaks-the-internet)