|Media type||High-density optical disc|
|Encoding||H.265/MPEG-H Part 2 (HEVC)|
|Capacity||50 GB (dual-layer, 92 Mb/s)|
66 GB (dual-layer, 123, 144 Mb/s)
100 GB (triple-layer, 123, 144 Mb/s)
|Block size||2 KB sector, 64 KB block size|
|Read mechanism||405 nm laser|
|Developed by||Blu-ray Disc Association|
|Dimensions||120 mm (4.7 in) diameter|
PlayStation 5 format software
|Extended from||Standard Blu-ray|
|Released||February 14, 2016|
Ultra HD Blu-ray (4K Ultra HD, UHD-BD, or 4K Blu-ray) is a digital optical disc data storage format that is an enhanced variant of Blu-ray. Ultra HD Blu-ray discs are incompatible with existing standard Blu-ray players. Ultra HD Blu-ray supports 4K UHD (3840 × 2160 pixel resolution) video at frame rates up to 60 progressive frames per second, encoded using High-Efficiency Video Coding. The discs support both high dynamic range by increasing the color depth to 10-bit per color and a greater color gamut than supported by conventional Blu-ray video by using the Rec. 2020 color space. Ultra HD Blu-Ray discs also support a 12-bit per color container via Dolby Vision. Dolby Vision content on 4K UHD Blu-Ray can also be mastered for 10,000 nits peak brightness, whereas standard HDR10 can only achieve a maximum of 4,000 nits of brightness. Moreover, Dolby Vision makes use of dynamic metadata, which adjusts the brightness and tone mapping per scene. In contrast, standard HDR10 only makes use of static metadata, which sets the same brightness and tone mapping for the entirety of the content.
The format is supported on Microsoft's Xbox One X, One S, Series X, and Sony's PlayStation 5. Software made for the PlayStation 5 can use 100 GB UHD Blu-ray discs.
To differentiate retail Ultra HD Blu-ray releases, the format usually uses a black opaque or slightly transparent keep case packaging format (as opposed to blue). The case size is the same as that of a normal Blu-ray disc.
The specification allows for three disc capacities, each with its own data rate: 50 GB at 72 or 92 Mbit/s, and 66 GB and 100 GB at 92, 123, or 144 Mbit/s. On 66 GB and 100 GB discs, the pits and lands are not narrower than those of a standard Blu-ray Disc, but shorter, which increases the capacity of each layer from 25 GB to 33 1/3 GB. This also means that each revolution of such a disc transfers more data than that of a standard Blu-ray Disc, which means the transfer rate is higher with the same linear velocity. In addition, the disc can be encoded to have the drive hold the full 5,000 rpm until it reaches a point slightly away from the innermost part of the disc if an even higher transfer rate is needed. 50 and 66 GB use two layers, and 100 GB uses three layers. Ultra HD Blu-ray technology was licensed in mid-2015, and players had an expected release date of Christmas 2015. Ultra HD Blu-ray uses a new revision of AACS DRM: AACS 2. In addition, AACS 2.1 is used on certain releases (Stand by Me, Fury, The Patriot, Zombieland).
On May 12, 2015, the Blu-ray Disc Association revealed completed specifications and the official Ultra HD Blu-ray logo. Unlike conventional DVDs and Blu-rays, the new 4K format does not have region coding.
On February 14, 2016, the BDA released Ultra HD Blu-ray with mandatory support for HDR10 Media Profile video and optional support for Dolby Vision.
On January 23, 2018, the BDA spec v3.2 gained optional support for HDR10+ and Philips and Technicolor's SL-HDR2, also known as Advanced HDR by Technicolor. However, no Ultra HD Blu-ray player has ever supported SL-HDR2, and no discs encoded in SL-HDR2 have been released.
Most retail Ultra HD Blu-ray discs are encoded with Ateme TITAN. Ultra HD Blu-ray discs use HDMV or BD-J for menus. Subtitles use Presentation Graphics Stream, which is the same format as normal Blu-ray discs.
Only computers with activated Software Guard Extensions (SGX) support Ultra HD Blu-ray playback. Intel introduced SGX in the Skylake generation Core processors in 2016, enabling PCs to play protected Blu-ray discs for the first time. In January 2022, Intel deprecated support for SGX for the Rocket Lake and Alder Lake generation desktop processors, leading to Ultra HD Blu-ray discs being unplayable on those systems.
The first Ultra HD Blu-ray Discs were officially released in the United States on February 14, 2016:
The following labels released their first Ultra HD Blu-rays in the United States after the format's introduction:
These were released by non-American companies.