Google said it would conduct an investigation of the outage and make appropriate improvements to the company's systems to prevent or minimize future recurrence.
Earlier on Sunday, Google said it was experiencing high levels of congestion, adding that the incident began at 3:25 p.m. EDT.
Google said it had identified the root cause, but did not elaborate.
Snapchat, which also experienced outages, said it was aware of the issue. DownDetector.com - an outage tracking website - showed that the number of Snapchat-related complaints had peaked at more than 48,000 before falling to about 1,800 as of 9 p.m. EDT on Sunday.
Snapchat's parent company, Snap Inc, said in its annual report it used Google Cloud, but neither company responded to questions about whether the Snapchat outage was linked to the Google Cloud issues.During the outage, many users took to Twitter to complain about it under the hashtag #YouTubeDOWN.
"When Snapchat and YouTube are both down and you don't know where to go next #YouTubeDOWN #snapchatdown," a user going by the name Jasmine tweeted.