Grande and Davidson are said to have split over the weekend, TMZ reported, citing sources.
People Magazine also confirmed that the pair has split.
"It was way too much too soon," a Grande source said. "It's not shocking to anyone."
Grande and Davidson were engaged in June after a few weeks of dating.
"We met on SNL, like, two, three years ago," Grande said of Davidson previously on The Tonight Show. "We never, like, exchanged numbers or anything, we weren't even friends for a long time, but I had the biggest crush in the whole world on him."
"I left and I jokingly said to my tour manager, I was like, 'I'm marrying him, 100 percent.' I was like, 'I'm literally marrying him,'" she continued.
Grande got together with Davidson following her relationship with rapper Mac Miller, who died in September. Grande honored Miller on social media and then announced through her rep that she would be taking some time off.
"Given the events of the past couple of years, Ariana is going to take some much needed time to heal and mend," the rep said in a statement. "She will be staying close to home and using this period to spend time with her loved ones and work on new music without deadline. She thanks her fans for their understanding."
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Celebrity breakups of 2018