As the biggest YouTuber out there, MrBeast is known for his eye-catching thumbnails. However, he recently noted one change that is causing even more people to view his videos. The 25-year-old - whose real name is Jimmy Donaldson - has over 181m subscribers and so knows what causes viewers to click on his latest piece of elaborate content. Often, MrBeast - like many other YouTubers - can be seen pulling a shocked face to attract and intrigue viewers to watch in his thumbnail images. But after testing out different versions for his videos, he shared how the classic pose isn't as effective as he thought, explaining that thumbnails with his mouth shut do better. “I closed my mouth on all my thumbnails and the watch time went up on every video lol,” MrBeast said on Twitter/X. “My mouth is now closed in all my thumbnails but the war has just begun. We must not rest until mouths are closed in everyone’s thumbnails." In the tweet, he shared a screenshot of the different combinations where YouTube declared the thumbnails of him flashing a smile were a "winner," compared to the traditional shocked face. "Now all YouTubers will shut their mouths," one user jokingly tweeted, to which the MrBeast replied: "Thank god." When someone asked the YouTuber if the shocked face thumbnail era was over, he answered: "Seems like it, here’s more results. Now that I can actually A/B test thumbnails I don’t have to guess and I just test and see what people want." The YouTuber admitted: "My mouth would have closed years ago if I had this tool." Sign up to our free Indy100 weekly newsletter Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.