YouTube

==== Quality and formats ====

YouTube originally offered videos at only one quality level, displayed at a resolution of 320×240 [[pixel]]s using the [[Sorenson codec|Sorenson Spark]] codec (a variant of [[H.263]]),<ref name="incomplete-h263">{{cite web |url=https://www.kaourantin.net/2005/08/quest-for-new-video-codec-in-flash-8.html |title=The quest for a new video codec in Flash 8 |first=Tinic |last=Uro |quote=We went this route before with Sorenson Spark which is an incomplete implementation of H.263 and it bit us badly when trying to implement certain solutions. |date=August 13, 2005 |access-date=January 27, 2011 |url-status=dead |archive-url=https://web.archive.org/web/20090206142709/https://kaourantin.net/2005/08/quest-for-new-video-codec-in-flash-8.html |archive-date=February 6, 2009}}</ref><ref name="flash-video">{{cite web |url=https://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf |title=Adobe Flash Video File Format Specification Version 10.1 |publisher=Adobe Systems Incorporated |page=72 |quote=Sorenson H.263 |year=2010 |access-date=January 27, 2011 |archive-date=December 19, 2011 |archive-url=https://web.archive.org/web/20111219144646/http://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf |url-status=live }}</ref> with mono MP3 audio.<ref>{{cite web |url=https://www.sorensonmedia.com/news/?n=379 |title=Market Demand for Sorenson Media's Sorenson Spark Video Decoder Expands Sharply |publisher=Sorenson Media |date=June 2, 2009 |access-date=July 31, 2009 |archive-url=https://web.archive.org/web/20090827160021/https://www.sorensonmedia.com/news/?n=379 |archive-date=August 27, 2009 |url-status=dead}}</ref> In June 2007, YouTube added an option to watch videos in [[3GP and 3G2|3GP]] format on mobile phones.<ref>{{cite web |url=https://www.downloadsquad.com/2007/06/17/youtube-mobile-goes-live/ |title=YouTube Mobile goes live |date=June 17, 2007 |access-date=August 11, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20070620083032/https://www.downloadsquad.com/2007/06/17/youtube-mobile-goes-live/ |archive-date=June 20, 2007}}</ref> In March 2008, a high-quality mode was added, which increased the resolution to 480×360 pixels.<ref>{{cite web |title=YouTube Videos in High Quality |url=https://youtube.googleblog.com/2008/03/youtube-videos-in-high-quality.html |website=Official YouTube Blog |date=March 14, 2008 |access-date=March 25, 2017 |archive-date=November 11, 2020 |archive-url=https://web.archive.org/web/20201111220719/https://youtube.googleblog.com/2008/03/youtube-videos-in-high-quality.html |url-status=live }}</ref> In December 2008, [[720p]] [[high-definition video|HD]] support was added. At the time of the 720p launch, the YouTube player was changed from a [[4:3]] [[aspect ratio (image)|aspect ratio]] to a [[widescreen]] [[16:9]].<ref>{{cite web |first=Josh |last=Lowensohn |title=YouTube videos go HD with a simple hack |url=https://www.cnet.com/news/youtube-videos-go-hd-with-a-simple-hack/ |publisher=[[CNET]] |date=November 20, 2008 |access-date=March 25, 2017 |archive-date=January 6, 2021 |archive-url=https://web.archive.org/web/20210106152302/https://www.cnet.com/news/youtube-videos-go-hd-with-a-simple-hack/ |url-status=live }}</ref> With this new feature, YouTube began a switchover to [[H.264/MPEG-4 AVC]] as its default video compression format. In November 2009, [[1080p]] HD support was added. In July 2010, YouTube announced that it had launched a range of videos in [[4K resolution|4K]] format, which allows a resolution of up to 4096×3072 pixels.<ref>{{cite web |first=Ramesh |last=Sarukkai |title=What's bigger than 1080p? 4K video comes to YouTube |url=https://youtube.googleblog.com/2010/07/whats-bigger-than-1080p-4k-video-comes.html |website=Official YouTube Blog |date=July 9, 2010 |access-date=March 25, 2017 |archive-date=November 12, 2020 |archive-url=https://web.archive.org/web/20201112041523/https://youtube.googleblog.com/2010/07/whats-bigger-than-1080p-4k-video-comes.html |url-status=live }}</ref><ref>{{cite web |first=Josh |last=Lowensohn |title=YouTube now supports 4K-resolution videos |url=https://www.cnet.com/news/youtube-now-supports-4k-resolution-videos/ |publisher=[[CNET]] |date=July 9, 2010 |access-date=March 25, 2017 |archive-date=August 11, 2019 |archive-url=https://web.archive.org/web/20190811145936/https://www.cnet.com/news/youtube-now-supports-4k-resolution-videos/ |url-status=live }}</ref> In July 2010, support for [[2160p]] UHD was added, with the videos playing at 3840 × 2160 pixels.<ref>{{cite web |title=YouTube Announces Partner Grants Program, Support For 4K Video Resolution |url=https://techcrunch.com/2010/07/09/youtube-partner-program-4k/ |website=TechCrunch |access-date=December 27, 2021 |date=July 9, 2010 |archive-date=December 27, 2021 |archive-url=https://web.archive.org/web/20211227010116/https://techcrunch.com/2010/07/09/youtube-partner-program-4k/ |url-status=live }}</ref> In June 2014, YouTube began to deploy support for [[high frame rate]] videos up to 60 [[frames per second]] (as opposed to 30 before), becoming available for user uploads in October. YouTube stated that this would enhance "motion-intensive" videos, such as [[video game]] footage.<ref>{{cite news |last=Brunner |first=Grant |date=June 27, 2014 |title=Will 60fps YouTube videos force game developers to prioritize frame rate? |url=https://www.extremetech.com/gaming/185454-will-60fps-youtube-videos-force-game-developers-to-prioritize-frame-rate |access-date=November 14, 2019 |website=ExtremeTech |archive-date=March 8, 2021 |archive-url=https://web.archive.org/web/20210308090441/https://www.extremetech.com/gaming/185454-will-60fps-youtube-videos-force-game-developers-to-prioritize-frame-rate |url-status=live }}</ref><ref>{{cite web |url=https://www.theverge.com/2014/10/29/7121143/youtube-adds-support-for-60fps-video-playback |title=YouTube now supports 60fps playback, and video games look amazing |last=Welch |first=Chris |date=October 29, 2014 |website=The Verge |language=en |access-date=November 14, 2019 |archive-date=March 8, 2021 |archive-url=https://web.archive.org/web/20210308101734/https://www.theverge.com/2014/10/29/7121143/youtube-adds-support-for-60fps-video-playback |url-status=live }}</ref><ref>{{cite news |url=https://www.theguardian.com/technology/2014/jun/27/battlefield-hardline-youtube-trailers-games |title=Battlefield Hardline ushers in era of smooth YouTube trailers |work=[[The Guardian]] |date=June 27, 2014 |access-date=June 29, 2014 |first=Keith |last=Stuart |archive-date=March 8, 2021 |archive-url=https://web.archive.org/web/20210308103930/https://www.theguardian.com/technology/2014/jun/27/battlefield-hardline-youtube-trailers-games |url-status=live }}</ref><ref>{{cite web |first=Greg |last=Kumparak |title=YouTube Can Now Play Videos at a Buttery 60 Frames Per Second |url=https://techcrunch.com/2014/10/29/60-fps-youtube/ |website=[[TechCrunch]] |publisher=[[AOL]] |date=October 29, 2014 |access-date=March 26, 2017 |archive-date=February 24, 2021 |archive-url=https://web.archive.org/web/20210224160242/https://techcrunch.com/2014/10/29/60-fps-youtube/ |url-status=live }}</ref> In June 2015, support for [[8K resolution]] was added, with the videos playing at 7680×4320 pixels.<ref>{{cite news |url=https://mashable.com/2015/06/10/youtube-8k-video/ |title=You can watch an 8K video on YouTube – in theory |publisher=MashableUK |date=June 10, 2015 |access-date=July 2, 2015 |first=Stan |last=Schroeder |archive-date=July 3, 2015 |archive-url=https://web.archive.org/web/20150703043235/http://mashable.com/2015/06/10/youtube-8k-video/ |url-status=live }}</ref> In November 2016, support for [[High-dynamic-range video|HDR video]] was added which can be encoded with [[hybrid log–gamma]] (HLG) or [[perceptual quantizer]] (PQ).<ref>{{cite web |first1=Steven |last1=Robertson |first2=Sanjeev |last2=Verma |title=True colors: adding support for HDR videos on YouTube |url=https://youtube.googleblog.com/2016/11/true-colors-adding-support-for-hdr.html |website=Official YouTube Blog |date=November 7, 2016 |access-date=March 25, 2017 |archive-date=June 14, 2020 |archive-url=https://web.archive.org/web/20200614154512/https://youtube.googleblog.com/2016/11/true-colors-adding-support-for-hdr.html |url-status=live }}</ref> HDR video can be encoded with the [[Rec. 2020]] color space.<ref>{{cite web |title=Upload High Dynamic Range (HDR) videos |url=https://support.google.com/youtube/answer/7126552 |website=YouTube Help |access-date=March 25, 2017 |archive-date=February 3, 2021 |archive-url=https://web.archive.org/web/20210203175756/https://support.google.com/youtube/answer/7126552 |url-status=live }}</ref>

YouTube videos are available in a range of quality levels. Viewers only indirectly influence the video quality. In the mobile apps, users choose between "Auto", which adjusts resolution based on the internet connection, "High Picture Quality" which will prioritize playing high-quality video, "Data saver" which will sacrifice video quality in favor of low data usage and "Advanced" which lets the user choose a stream resolution.<ref>{{cite web |date=April 25, 2021 |title=How to adjust adjust video quality on YouTube |url=https://indianexpress.com/article/technology/tech-news-technology/youtube-new-video-quality-settings-explained-7287426/ |access-date=May 30, 2021 |website=The Indian Express |language=en |archive-date=June 2, 2021 |archive-url=https://web.archive.org/web/20210602215246/https://indianexpress.com/article/technology/tech-news-technology/youtube-new-video-quality-settings-explained-7287426/ |url-status=live }}</ref> On desktop, users choose between "Auto" and a specific resolution.<ref>{{cite web |title=Change the quality of your video – YouTube Help |url=https://support.google.com/youtube/answer/91449?hl=en&ref_topic=9257411 |access-date=December 29, 2021 |publisher=Google Inc. |archive-date=December 29, 2021 |archive-url=https://web.archive.org/web/20211229191924/https://support.google.com/youtube/answer/91449?hl=en&ref_topic=9257411 |url-status=live }}</ref> It is not possible for the viewer to directly choose a higher [[bitrate]] (quality) for any selected resolution.

Since 2009, viewers have had the ability to watch 3D videos.<ref>{{cite web |date=July 21, 2009 |title=YouTube in 3D |url=https://www.youtube.com/watch?v=5ANcspdYh_U |archive-url=https://ghostarchive.org/varchive/youtube/20211221/5ANcspdYh_U |archive-date=December 21, 2021 |url-status=live |access-date=August 3, 2009 |via=YouTube}}{{cbignore}}</ref> In 2015, YouTube began natively supporting [[360-degree video]]. Since April 2016, it allowed live streaming 360° video, and both normal and 360° video at up to 1440p, and since November 2016 both at up to 4K (2160p) resolution.<ref>{{cite news |last=Bonnington |first=Christina |date=March 13, 2015 |title=You Can Now Watch and Upload 360-Degree Videos on YouTube |language=en-US |magazine=Wired |url=https://www.wired.com/2015/03/youtube-360-degree-video/ |access-date=May 10, 2021 |issn=1059-1028 |archive-date=July 9, 2016 |archive-url=https://web.archive.org/web/20160709080447/http://www.wired.com/2015/03/youtube-360-degree-video/ |url-status=live }}</ref><ref name="Verge 2016" /><ref>{{cite web |url=https://youtube-eng.googleblog.com/2016/04/new-youtube-live-features-live-360.html |title=New YouTube live features: live 360, 1440p, embedded captions, and VP9 ingestion |website=googleblog.com |publisher=YouTube Engineering and Developers Blog |access-date=December 26, 2021 |language=en |date=April 19, 2016 |archive-date=December 1, 2021 |archive-url=https://web.archive.org/web/20211201205447/https://youtube-eng.googleblog.com/2016/04/new-youtube-live-features-live-360.html |url-status=dead}}</ref> Citing the limited number of users who watched more than 90-degrees, it began supporting an alternative stereoscopic video format known as VR180 which it said was easier to produce,<ref>{{cite news |title=YouTube's "VR180" format cuts down on VR video's prohibitive requirements |language=en-us |work=Ars Technica |url=https://arstechnica.com/gadgets/2017/06/youtubes-vr180-format-makes-vr-video-more-accessible/ |access-date=September 26, 2017 |archive-date=March 16, 2021 |archive-url=https://web.archive.org/web/20210316035205/https://arstechnica.com/gadgets/2017/06/youtubes-vr180-format-makes-vr-video-more-accessible/ |url-status=live }}</ref> which allows users to watch any video using virtual reality headsets.<ref>{{cite web |last=Broida |first=Rick |title=Watch any YouTube video in VR mode |url=https://www.cnet.com/how-to/watch-any-youtube-video-in-vr-mode/ |access-date=May 10, 2021 |publisher=CNET |language=en |archive-date=May 11, 2021 |archive-url=https://web.archive.org/web/20210511133658/https://www.cnet.com/how-to/watch-any-youtube-video-in-vr-mode/ |url-status=live }}</ref>

In response to increased viewership during the COVID-19 pandemic, YouTube temporarily downgraded the quality of its videos.<ref>{{cite news |title=YouTube, Amazon and Netflix cut picture quality in Europe |url=https://www.ft.com/content/70333747-f180-4887-8a26-27ab6b230299 |access-date=March 20, 2020 |work=Financial Times |date=March 20, 2020 |last1=Espinoza |first1=Javier |last2=Fildes |first2=Nic |last3=Murphy |first3=Hannah |last4=Bradshaw |first4=Tim |archive-date=March 8, 2021 |archive-url=https://web.archive.org/web/20210308010939/https://www.ft.com/content/70333747-f180-4887-8a26-27ab6b230299 |url-status=live }}</ref><ref>{{cite web |last=Alexander |first=Julia |date=March 24, 2020 |title=YouTube is reducing its default video quality to standard definition for the next month |url=https://www.theverge.com/2020/3/24/21192384/youtube-video-quality-reduced-hd-broadband-europe-streaming |access-date=October 20, 2020 |website=The Verge |archive-date=February 1, 2021 |archive-url=https://web.archive.org/web/20210201043737/https://www.theverge.com/2020/3/24/21192384/youtube-video-quality-reduced-hd-broadband-europe-streaming |url-status=live }}</ref> YouTube developed its own chip, called Argos, to help with encoding higher resolution videos in 2021.<ref>{{cite web |last=Shankland |first=Stephen |title=Google supercharges YouTube with a custom video chip |url=https://www.cnet.com/news/google-supercharges-youtube-with-a-custom-video-chip/ |access-date=May 5, 2021 |publisher=CNET |language=en |archive-date=May 5, 2021 |archive-url=https://web.archive.org/web/20210505173316/https://www.cnet.com/news/google-supercharges-youtube-with-a-custom-video-chip/ |url-status=live }}</ref>

In April 2023, YouTube began offering some videos in an enhanced bitrate "[[1080p]] Premium" option for YouTube Premium subscribers on iOS.<ref>{{Cite web |last=Roth |first=Emma |date=April 10, 2023 |title=YouTube is giving Premium subscribers higher-quality video than everyone else |url=https://www.theverge.com/2023/4/10/23677141/youtube-premium-subscribers-higher-quality-video-1080p |access-date=April 10, 2023 |website=The Verge |language=en-US |archive-date=December 10, 2023 |archive-url=https://web.archive.org/web/20231210124330/https://www.theverge.com/2023/4/10/23677141/youtube-premium-subscribers-higher-quality-video-1080p |url-status=live }}</ref> In August 2023, the feature became available to subscribers on desktop platforms.<ref>{{cite web |last1=Peters |first1=Jay |title=YouTube's 'enhanced' 1080p for Premium subscribers is now available on desktop web |url=https://www.theverge.com/2023/8/4/23820482/youtube-enhanced-bitrate-1080p-premium-desktop-web-living-room |website=The Verge |date=August 4, 2023 |access-date=December 23, 2023 |archive-date=December 7, 2023 |archive-url=https://web.archive.org/web/20231207200835/https://www.theverge.com/2023/8/4/23820482/youtube-enhanced-bitrate-1080p-premium-desktop-web-living-room |url-status=live }}</ref>

In certain cases, YouTube allows the uploader to upgrade the quality of videos uploaded a long time ago in poor quality. One such partnership with [[Universal Music Group]] included remasters of 1,000 music videos.<ref>{{cite web |last=Perez |first=Sarah |title=YouTube partners with Universal to upgrade nearly 1,000 classic music videos to HD |url=https://techcrunch.com/2019/06/19/youtube-partners-with-universal-to-upgrade-nearly-1000-classic-music-videos-to-hd/ |date=June 19, 2019 |access-date=March 9, 2022 |website=TechCrunch |language=en |archive-date=March 9, 2022 |archive-url=https://web.archive.org/web/20220309091746/https://techcrunch.com/2019/06/19/youtube-partners-with-universal-to-upgrade-nearly-1000-classic-music-videos-to-hd/ |url-status=live }}</ref>