16:9 (1.7 7 :1) (16:9 = 4 2 :3 2 ) is an aspect ratio with a width of 16 units and height of 9. Since 2010 it has become the most common aspect ratio for televisions and computer monitors, and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television. This has replaced the old 4:3 aspect ratio.
Dr. Kerns H. Powers, a member of the SMPTE Working Group on High-Definition Electronic Production, first proposed the 16:9 (1.7 7 :1) aspect ratio at a time when nobody was creating 16:9 videos. The popular choices in 1980 were: 1.3 3 :1 (based on television standard's ratio at the time), 1.6 6 :1 (the European "flat" ratio), 1.85:1 (the American "flat" ratio), 2.20:1 (the ratio of 70 mm films and Panavision) and 2.39:1 (the CinemaScope ratio for anamorphic widescreen films).
Powers cut out rectangles with equal areas, shaped to match each of the popular aspect ratios. When overlapped with their center points aligned, he found that all of those aspect ratio rectangles fit within an outer rectangle with an aspect ratio of 1.7 7 :1 and all of them also covered a smaller common inner rectangle with the same aspect ratio 1.7 7 :1.  The value found by Powers is exactly the geometric mean of the extreme aspect ratios, 4:3 (1.3 3 :1) and 2.35:1 (or 64:27, see also 21:9 aspect ratio for more information), √ 47 / ≈ 1.770 which is coincidentally close to 16:9 (1.7 7 :1). Applying the same geometric mean technique to 16:9 and 4:3 yields the 14:9 aspect ratio, which is likewise used as a compromise between these ratios.
While 16:9 (1.7 7 :1) was initially selected as a compromise format, the subsequent popularity of HDTV broadcast has solidified 16:9 as perhaps the most important video aspect ratio in use. Most 4:3 (1.3 3 :1) and 2.39:1 video is now recorded using a " shoot and protect " technique  that keeps the main action within a 16:9 (1.7 7 :1) inner rectangle to facilitate HD broadcast. Conversely it is quite common to use a technique known as center-cutting, to approach the challenge of presenting material shot (typically 16:9) to both a HD and legacy 4:3 audience simultaneously without having to compromise image size for either audience. Content creators frame critical content or graphics to fit within the 1.33 raster space. This has similarities to a filming technique called Open matte.
After the original 16:9 Action Plan of the early 1990s, the European Union has instituted the 16:9 Action Plan,  just to accelerate the development of the advanced television services in 16:9 aspect ratio, both in PAL and also in HDTV. The Community fund for the 16:9 Action Plan amounted to € 228 million.
In 2008 the computer industry started switching to 16:9 as the standard aspect ratio for monitors and laptops. A 2008 report by DisplaySearch cited a number of reasons for this shift, including the ability for PC and monitor manufacturers to expand their product ranges by offering products with wider screens and higher resolutions, helping consumers to more easily adopt such products and "stimulating the growth of the notebook PC and LCD monitor market". 
In 2011 Bennie Budler, product manager of IT products at Samsung South Africa, confirmed that monitors capable of 1920×1200 resolutions aren't being manufactured anymore. "It is all about reducing manufacturing costs. The new 16:9 aspect ratio panels are more cost effective to manufacture locally than the previous 16:10 panels".  Since computer displays are advertised by their diagonal measure, for monitors with the same display area, a wide screen monitor will have a larger diagonal measure, thus sounding more impressive. Within limits, the amount of information that can be displayed, and the cost of the monitor depend more on area than on diagonal measure.
16:9 is the only widescreen aspect ratio natively supported by the DVD format. Anamorphic DVD transfers store the information as 5:4 (PAL) or 3:2 (NTSC) square pixels, which is set to expand to either 16:9 or 4:3, which the television or video player handles. For example, a PAL DVD with a full frame image may contain a video resolution of 720×576 (5:4 ratio), but a video player software will stretch this to 1024×576 square pixels with a 16:9 flag in order to recreate the correct aspect ratio.
DVD producers can also choose to show even wider ratios such as 1.85:1 and 2.39:1 within the 16:9 DVD frame by hard matting or adding black bars within the image itself. Some films which were made in a 1.85:1 aspect ratio, such as the U.S.-Italian co-production Man of La Mancha and Kenneth Branagh's Much Ado About Nothing , fit quite comfortably onto a 1.7 7 :1 HDTV screen and have been issued anamorphically enhanced on DVD without the black bars. Many digital video cameras have the capability to record in 16:9.
Super 16 mm film is frequently used for television production due to its lower cost, lack of need for soundtrack space on the film itself, and aspect ratio similar to 16:9.
Common resolutions for 16:9 are listed in the table below:
|4096||2304||Full 4K UHD|
|8192||4608||Full 8K UHD|
In Europe, 16:9 is the standard broadcast format for most digital channels and all HDTV broadcasts. Some countries adopted the format for analog television, first by using the PALplus standard (now obsolete) and then by simply using WSS signals on normal PAL broadcasts.
Older programmes filmed in 4:3 are:
**transmitted in their original format.
And almost all pay channels via TNT, ADSL, DVB-C and DVB-S ;
Canal+ Décalé, Canal+ Family, Poker Channel, CinePlay, Ciné Cinéma Premier, OL TV, Motors TV, Disney Cinemagic, Disney Cinemagic + 1, NRJ Hits, Ciné Cinéma Premier HD and SD, National Geographic HD and SD, Ushuaia TV HD and SD, Disney Cinemagic HD and SD, MTV HD, NRJ 12 HD and SD, iConcert HD, HD1, Melody Zen HD, Sci Fi Channel HD and SD, 13ème Rue HD and SD, Orange cinemax HD etc. Germany All channels. Georgia GPB (1TV, 2TV), Maestro TV, Kavkasia TV, Tabula TV, GDS TV, Voice of Abkhazia, Ajara TV, Pirveli TV, Marao TV, Aratrea TV. Greece All Channels. Hungary All channels (except Cartoon Network, Boomerang, Echo TV, Pax TV) Iceland All three national stations broadcast in 16:9 with occasional 4:3 programmes. Local stations still use 4:3. Ireland RTÉ channels, TV3, TG4, and Eir Sport. Italy All Channels. Kazakhstan All channels. Latvia Always on 16:9 : Latvijas Televīzija ( LTV1, LTV7), Re:TV, TV24, SportaCentrs.tv, TV XXI.
Lithuania Always on 16:9 : LRT channels ( LRT televizija, LRT Kultūra, LRT Lituanica), Sport1 (Lithuania), Lietuvos rytas TV, Balticum TV, Balticum Auksinis.
Luxembourg RTL Télé Lëtzebuerg, Luxe.tv. Macedonia All Channels Malta All nationwide channels. Moldova TRM (Moldova 1, Moldova 2), GMG Group (Prime, Canal 2, Canal 3, Publika TV), ProTV Chishinau, N4, Jurnal TV Monaco Télé Monte Carlo & Monaco Info. Montenegro All Channels Netherlands All Channels Norway 16:9 is the national standard for television – almost all channels conform to this format. Poland All Channels Portugal All Channels. Romania All Channels Russia All channels switch in 1 September 2017 San Marino San Marino RTV Serbia All Channels. Slovakia All nationwide channels ( RTVS, CME Slovakia, J&T, TA3 and others). Slovenia All Channels. Spain All Channels Sweden All Channels. Switzerland All Channels. Turkey All Channels. Ukraine 1+1 Media Group (all channels), Inter Media Group (all channels), StarLightMedia (except Novyi Kanal), Media Group Ukraine (except Eskulap TV), 5 kanal, Channel 24, ZIK, 112 Ukraine, Espreso TV, Pryamiy, News One, NewsNetwork, Pershiy Diloviy, ATR Group ( ATR, Lale), XSPORT, Black Sea TV, Poverkhnost TV (Sport 1, Sport 2), Music Box Ukraine, EU Music, Trofey TV, Dacha TV, HDFashion, RTI, PravdaTut, UATV, English Club TV. United Kingdom In 1998, with the introduction of digital television, digital versions of BBC One, BBC Two, ITV and Channel 4 were created. An On Digital set top box or a subscription to Sky Digital was required to view the digital versions.
On 1 July 2000, " C-Day ", most of the UK broadcast industry began requiring commercials to be delivered in 16:9 full-height format (with a 14:9 safe area for those channels still broadcasting in 4:3). ITV and C4 upgraded their continuity suites to be 16:9 capable at the same time, allowing idents to be broadcast in widescreen format on digital.
In 2001, the UK's fourth broadcaster Channel 5 switched to 16:9.
In 2002, On Digital became defunct and free-to-air digital terrestrial television services instead began to operate under the name of Freeview.
In 2003, Sky branded channels were re-branded which included the switch to 16:9.
In 2006, BBC HD began broadcasting in 1080i which became the standard for all HD channels. Similar to the switch to Digital in 1998, viewers using terrestrial services required an additional set-top-box which was HD capable
In 2007, Channel 4 HD was launched on Sky. It was later added to Virgin Media in 2009 and then to Freeview HD in 2011.
In 2008, ITV HD was launched on Freesat and was later added to Virgin Media, Sky and Freeview HD in 2010.
In 2009, Freeview HD launched allowing terrestrial viewers to watch BBC HD and ITV HD without a subscription, a Freeview HD set-top box or television is required.
In 2010, Channel 5 HD was launched on Sky and Virgin Media.
In 2011, BBC One HD was launched on Sky, Virgin Media and Freeview HD. As of 2012,
All Freeview channels broadcast in 16:9;
Almost all Virgin Media/Sky channels broadcast in 16:9. The rest switched by the end of 2012. Older 4:3 programmes are either shown in their original format or zoomed to 14:9 or 16:9.
|Australia||All major free to air channels and almost all pay TV channels (including SD). Older 4:3 programmes are either shown in their original format or zoomed to 14:9 or 16:9.|
|New Zealand||All channels.|
Japan's Hi-Vision originally started with a 5:3 ratio but converted when the international standards group introduced a wider ratio of 5 1 ⁄ 3 to 3 (=16:9).
|China||CCTV channels 1-15, CCTV-5+, CCTV News. Older contents in 4:3 and news contents are stretched on SD variants of these channels as stretching on SD channels is common.|
|Hong Kong||All major channels since digital television broadcasting started in 2007.|
|Indonesia|| 16:9 native * : Kompas TV, BeritaSatu TV ** , CNN Indonesia *** , ntv (Nusantara TV) **** , InspiraTV **** , MetroTV |
*Channels that are primarily broadcast in 16:9 sometimes are filled by 4:3 content which are either stretched or pillarboxed.
**Only on digital cable/satellite.
***Only on digital cable/satellite. When broadcasting on Trans TV (and sometimes on Trans7 as well), this channel follows broadcast configuration of Trans TV.
****Only on digital terrestrial.
*****Channels in this category broadcast in 16:9 HDTV along with inner 4:3 SDTV at the same time. Due to their visibility, some contents are either pillarboxed and windowboxed (especially in commercial ads). Wider contents are usually letterboxed.
******These channels are still using 4:3 configuration. Wider contents are either squashed, pan-and-scanned, or letterboxed. When broadcasting on recent TV devices or internet in 16:9 format, all SD channels (or SD mode of HD channel in some cases) are stretched.
Note: Nationwide TV channels listed above are classified according to their original configuration. Configuration for exclusive channels from digital cable provider, local channels, and local version of nationwide channels are may vary.
|Israel||All main channels, including but not limited to Hot & Yes.|
|Japan||Japan pioneered in its analogue HDTV system ( MUSE) in 16:9 format, started in the 1980s. Currently all main channels have digital terrestrial television channels in 16:9 while being simulcast in analogue 4:3 format. Many satellite broadcast channels are being broadcast in 16:9 as well.|
|Lebanon||LBCI.4:3 Shows are stretched|
|Mongolia||MNB & MN2, MNC, Edutainment TV, SPS and Sportbox.|
|Philippines|| 16:9 native * : CNN Philippines, Hope Channel Philippines, 3ABN , Hope International, INCTV, Net 25 |
4:3 upscaled/stretched to 16:9 ** : ETC, 2nd Avenue, GMA Network, GMA News TV, all BEAM's subchannels, Light Network, UNTV, Ang Dating Daan TV, SMNI, all ABS-CBN channels (including TVPlus channels), TV5, AksyonTV
*channels that are letterboxed on analog terrestrial transmissions nor no letterbox on widescreen-produced programs.
**channels that are originally broadcasting in 4:3 on analog terrestrial, but upscaled or stretched to 16:9 for digital terrestrial television, cable and satellite.
|Qatar||All Al Jazeera Sports channels, Al Jazeera, Al Jazeera English, Qatar TV HD, all Alkass channels.|
|Saudi Arabia||All channels.|
|Singapore||All MediaCorp channels, however 16:9 contents look squashed on older 4:3 sets. Also, all 4:3 contents including news clips are stretched as stretching is common.|
|South Korea||All major channels currently feature 16:9 aspect ratio.|
|Sri Lanka||Colombo TV.|
|Taiwan||TTV HD, CTV HD, CTS HD, FTV HD, PTS HD, TVBS.|
|United Arab Emirates||All channels.|
|Vietnam||All of VTC HD's channels, VTV channels, HTV channels and K+'s channels (selected programmes).|
In the Americas
|Bolivia|| Always on 16:9 : PAT, ATB. |
Often on 16:9 : Bolivia TV.
|Brazil||Rede Bandeirantes, Rede Globo, Rede Record, Rede Gazeta, Rede TV!, SBT, FOX Sports, ESPN, ESPN Brasil, ESPN+, Telecine Premium, Telecine Action, Telecine Touch, Telecine Pipoca, Telecine Fun, Telecine Cult, Multishow, GNT, HBO, HBO HD, MAX HD, Gloob, Arte1, Megapix Sky Esportes, Canal Off, BIS, Canal Sony, History Channel, TBS, AXN, +Globosat, Warner Channel, Discovery Channel etc.|
|Canada||Almost all channels.|
|Chile||Canal 13HD, Chilevisión HD, TVN HD, MEGA HD.|
|Colombia||All channels, except Citytv|
|Costa Rica||All channels.|
|Mexico||Free Television : Las Estrellas, FOROtv, Canal 5, Gala TV, Azteca 7, Azteca Trece, adn40, Canal Once, Canal 22, Una Voz con Todos, Teveunam, Imagen Televisión, Excélsior TV, Televisa Regional, Multimedios Televisión, Milenio Televisión, Teleritmo, and some local stations broadcast HD signal.|
|United States||Almost all channels.|
|South Africa||16:9 is the standard broadcast format for most digital channels and all HDTV broadcasts all main channels.|
- Display aspect ratio
- High-definition television
- Display resolution
- 1080p / 1080i