Reddit users have recently discovered that YouTube refuses to stream newly uploaded 4K video in its native resolution if the website is accessed through Safari web browser.

The issue was first raised almost a month ago by Reddit user GezimS, who wondered why the option to view 4K videos in 2160p was no longer available.

YouTube 4K
Other users soon chimed in to confirm the anomaly, noting that it only seemed to occur in recently uploaded 4K video and that accessing the same content in Chrome or Firefox still offered up the preferred 2160p resolution as a viewing option.

After some digging, user themcfly recently discovered that the issue is being caused by a change to the way YouTube encodes video and serves it through its website.

Specifically, YouTube appears to be storing video on its servers using either the more efficient VP9 codec or the older H.264 codec. Safari only supports the latter, which explains why recently uploaded 4K videos are only able to be viewed in up to 1440p.

Funnily enough, the same videos can be streamed by Safari in native 4K as long as they're embedded in another website, suggesting that the VP9 codec support requirement only applies to videos viewed directly on YouTube's website.

Until Apple updates Safari to support the VP9 codec, Mac users who want to access newer 4K video on YouTube in native 2160p resolution are advised to use a different browser.

Tags: 4K, Safari, YouTube

Top Rated Comments

itsmilo Avatar
119 months ago
Safari is still the world's best browser. Safari alone is one of the best reasons you can have for choosing to use macOS and iOS.

Nothing compares to Safari when it comes to buttery smooth browsing experiences, world class security, privacy built-in, and obsessive attention to detail that delivers all of us a completely delightful experience every time.
Did you copy paste this from the product website?
Score: 6 Votes (Like | Disagree)
119 months ago
V9 is a horrible codec though, I hope Apple don't put it into Safari, and nor Firefox follow suit to prevent this adoption - they should be using the far better H.265, not only is it better quality but it's set to be the industry standard - the iPhone has already decoded it for two generations, many video cards enable efficient processing for it - V9 has none of this, there is no hardware decoding for what is (even if it had it) a worse codec.
New Kaby Lake processors have hardware decoding for VP9, calm down
Score: 5 Votes (Like | Disagree)
dumastudetto Avatar
119 months ago
Safari is still the world's best browser. Safari alone is one of the best reasons you can have for choosing to use macOS and iOS.

Nothing compares to Safari when it comes to buttery smooth browsing experiences, world class security, privacy built-in, and obsessive attention to detail that delivers all of us a completely delightful experience every time.
Score: 5 Votes (Like | Disagree)
iamMacPerson Avatar
119 months ago
*Article regarding macOS Safari*
*Posted on iOS Blog*

Anyway, it's getting hard to use Safari if Apple doesn't start supporting these newer formats. I understand the battery concerns, but it only needs to be enabled when a user wants to watch a video in 4K if done right. Although that might be a little bit more coding needed on YouTube's end instead of Apple's.

Still better then Chrome for battery efficiency.
Score: 3 Votes (Like | Disagree)
119 months ago
What am I missing? I just played 2 videos in 4K on my 2016 MBP using Safari. I searched "4K video" and played the 2 top search results at 2160p.o_O
Read the article. Not just the headline.
Score: 3 Votes (Like | Disagree)
AppleWarrior Avatar
119 months ago
Safari is still the world's best browser. Safari alone is one of the best reasons you can have for choosing to use macOS and iOS.

Nothing compares to Safari when it comes to buttery smooth browsing experiences, world class security, privacy built-in, and obsessive attention to detail that delivers all of us a completely delightful experience every time.
Seriously? I love the look of Safari, no doubt. And it is a good browser, but this adoration is unfounded. Safari stops working a lot. If you go to a website it will get stuck on its way there, and you have to shut the browser down and restart for it to operate normally again. And, if you had other tabs open that you navigated to throughout various searches, you lose them and have to find them again. This is extremely frustrating. Other browsers do not do this to me. So, I wouldn't call Safari a delightful experience every time, and that nothing compares to it.
Score: 3 Votes (Like | Disagree)

Popular Stories

Apple Announces Special Event in New York Feature 1

Apple Reportedly Plans to Unveil at Least Five New Products Next Week

Sunday February 22, 2026 9:48 am PST by
In his Power On newsletter today, Bloomberg's Mark Gurman said Apple will have a three-day stretch of product announcements from Monday, March 2 through Wednesday, March 4. In total, he expects Apple to introduce "at least five products." Subscribe to the MacRumors YouTube channel for more videos. A week ago, Apple invited selected journalists and content creators to an "Apple Experience" in...
iOS 26

iOS 26.3.1 Update for iPhones Coming Soon as 'Apple Experience' Nears

Sunday February 22, 2026 5:29 pm PST by
Apple's software engineers are testing iOS 26.3.1, according to the MacRumors visitor logs, which have been a reliable indicator of upcoming iOS versions. iOS 26.3.1 should be a minor update that fixes bugs and/or security vulnerabilities, and it will likely be released within the next two weeks. Last month, Apple released iOS 26.2.1 with bug fixes and support for the second-generation...
tim cook data privacy day

Tim Cook Warned by CIA That China Could Move on Taiwan by 2027

Tuesday February 24, 2026 4:03 am PST by
Apple CEO Tim Cook was among a handful of top tech executives who attended a classified CIA briefing warning that China could attack Taiwan by 2027, according to a sweeping investigative report by The New York Times ($). The previously unreported briefing was apparently held in a secure room in Silicon Valley in July 2023. The meeting is said to have been arranged at the request of the...