HDMI (High-Definition Multimedia Interface) is a proprietary specification designed to ensure compatibility between video and audio devices over a single digital interface. The specification is used for consumer electronics — including high-definition and ultrahigh-definition TVs, DVD and Blu-ray players, game consoles, streaming devices, soundbars, laptops and PCs — as well as for automotive and commercial devices. HDMI cables connect these devices and carry both uncompressed digital audio and video signals over a single cable.
HDMI is a brand name for a proprietary all-digital interface used for transmitting uncompressed digital video and audio data from a source device to a display or audiovisual (AV) receiver. It is a trademark of HDMI Licensing Administrator, Inc.
HDMI specifications include physical features, such as how cables and devices interface mechanically; electrical features, such as how much power the cable carries; and communication protocols, which describe what signals are sent over cables to enable two pieces of equipment to communicate.
The history of the HDMI specification
The first HDMI specification was released in December 2002. It was developed by a group of seven founding companies: Hitachi, Lattice Semiconductor Corp., Panasonic, Philips, Sony, Toshiba and Vantiva. These companies developed and released five major updates to the specification from 2002 to 2009. Since 2011, the HDMI Forum has been responsible for developing the HDMI specification and has continued to release further updates. The current version of the HDMI specification is 2.2.
The HDMI 1.x specifications included the following fundamental features:
- Audio Return Channel (ARC), which sends audio from a TV to an amplifier or AV receiver or soundbar.
- Multichannel digital audio formats.
- Three-dimensional (3D) video.
- Auto lip-sync, which synchronizes audio and video.
- Consumer Electronics Control commands, which enable a single remote to control multiple devices.
- Deep color.
The following are the first five releases of the HDMI specification:
- 2002. HDMI 1.0, which supported 4.95 gigabits per second (Gbps), or 1K@60, which is 1K resolution per frame, or 1920×1080 pixels at 60 frames per second.
- 2004. HDMI 1.1, which added support for DVD-Audio.
- 2005. HDMI 1.2, which added 1-bit audio for Super Audio CDs.
- 2006. HDMI 1.3, which supported 10.2 Gbps, or 4K@30, which is 4K resolution per frame, or 3840×2160 at 30 frames per second.
- 2009. HDMI 1.4, which added HDMI Ethernet Channel, ARC, 3D over HDMI, a new micro HDMI connector, an expanded set of colors and an automotive connection system (ACS).
What is the HDMI Forum?
HDMI Forum Inc. is a nonprofit corporation formed by the seven companies that developed the original HDMI specification to encourage broader industry participation in the development of future versions of the HDMI specification. The forum is currently made up of more than 90 companies, including manufacturers of consumer electronics, PCs, mobile devices, cables, components and test equipment. It also includes movie studios, service providers and test labs.
Since its inception in October 2011, the HDMI Forum has been responsible for all standardization activities, including the development and release of updates to the specification.
The HDMI Forum developed and released the following updates to the HDMI specification:
- 2013. HDMI 2.0, which supported 18 Gbps and 4K@60.
- 2017. HDMI 2.1, which supported 48 Gbps and 8K@60.
- 2022. HDMI 2.1a, which added support for Source-Based Tone Mapping.
- 2025. HDMI 2.2, which supports 96 Gbps and 8K@240 and 16K@60.
To improve the quality of HDMI cables, the forum added the Premium HDMI Cable Certification Program in 2015 and the Ultra HDMI Cable Certification Program in 2020.
What is included in the current version of the HDMI specification?
The HDMI 2.2 specification released in early 2025 supports higher video resolution and refresh rates, advanced high dynamic range (HDR) formats and bandwidth capacity of up to 96 Gbps. HDMI 2.2 is backward-compatible with earlier versions of HDMI technology.
The HDMI 2.2 specification offers considerable improvements over HDMI 2.1, including refresh rates of 4K at 480 hertz and 8K at 240 Hz. It requires the use of Ultra-High-Speed HDMI Cables, specifically the Ultra96 HDMI Cable, which must be certified under the Ultra HDMI Certification Program. The cables are tested to ensure bandwidth and protocol compliance and low electromagnetic interference (EMI) with other technology that might be operating nearby, including Bluetooth, Wi-Fi, mobile phones and streaming media players.
The HDMI 2.2 specification also includes the following features:
- Improved bandwidth. Doubling the bandwidth from HDMI 2.1 provides higher resolutions and refresh rates. HDMI 2.2 is designed to enhance data-intensive applications, like high-end gaming, augmented reality and virtual reality.
- Latency Indication Protocol. LIP is designed to improve audio and video synchronization for systems with soundbars or AV receivers.
What are the types of HDMI connectors?
HDMI technology includes five connector types, all defined in 1.x specifications. Types A and B were defined in the HDMI 1.0 specification, type C was defined in the HDMI 1.3 specification, and types D and E were defined in the HDMI 1.4 specification:
- Type A. The standard connector is the most widely used of the five HDMI connector types. It consists of 19 pins.
- Type B. The dual-link connector was developed for high-resolution displays using 21 pins. It’s electronically compatible with single-link Digital Visual Interface-Digital (DVI-D), but it has never been used by mainstream consumer products. The HDMI 1.3 specification exceeded the bandwidth of dual-link DVI-D, effectively rendering type B obsolete.
- Type C. The mini connector has the same 19-pin configuration and supports the same features as the type A connector but in a smaller, more compact form factor for use on portable devices, such as cameras and tablets. Some of the signals changed with respect to type A connectors, so a special converter cable is required to connect type A connectors to type C connectors.
- Type D. The micro connector has the same functionality as types A and C but is about half the width of the type C connector and is used in small, portable devices, such as phones. This connector uses 19 pins, but the pin assignment is different from types A and C. Type D connectors resemble micro USB connectors.
- Type E. The ACS for use inside vehicles has a locking tab to keep the cable in place despite vibrations and a shell to keep moisture and dirt from interfering with the signals.
HDMI Licensing Administrator maintains a list of approved connectors.
What are the types of HDMI cables?
HDMI cables are made up of four shielded twisted pairs and seven separate conductors. Those that support Ethernet include an additional shielded twisted pair made from three of the separate conductors.
Several HDMI cable types have been specified to meet different performance standards, along with cable certification designations. The current cable types and their performance are listed below from most recent to oldest. Certification designations are provided for cable specifications developed after 2015, the year the first cable certification program was launched:
- Ultra96 HDMI Cable. The latest cable supports up to 96 Gbps, exceeds international EMI standards and offers low magnetic interference. This cable supports 16K resolution at 60 Hz and 12K at 120 Hz. It is part of the Ultra HDMI Cable Certification Program.
- Ultra High Speed HDMI Cable. This supports up to 48 Gbps with exceptionally low EMI and is the only cable that supports all HDMI 2.1a features, including uncompressed digital video at 8K@60 and 4K@120. The cable packaging is required to display the Ultra High-Speed HDMI Cable Certification Label.
- Premium High Speed HDMI Cable and Premium High-Speed HDMI Cable with Ethernet. These cables support up to 18 Gbps with low EMI and advanced features, including 4K@60, HDR and expanded color spaces. The cable packaging is required to display HDMI Licensing Administrator’s Premium HDMI Cable Certification Label.
- High Speed HDMI Cable with Ethernet. This supports up to 10.2 Gbps and is the same as High Speed HDMI except that it has an additional data channel, called HDMI Ethernet Channel, dedicated to Ethernet networking.
- High Speed HDMI Cable. This supports up to 10.2 Gbps and is designed to handle advanced display technologies, such as 4K@30, 3D and deep color. It is recommended for connecting a 1080p HD display to a 1080p HD content source, such as a Blu-ray Disc player.
- High Speed Automotive HDMI Cable. This is designed to connect with an automotive system and needs to send a stronger signal than other cable types. It might also use a special dust- and vibration-resistant HDMI type E connector with a locking tab.
- Standard HDMI Cable with Ethernet. This is the same as Standard HDMI Cables, except that it offers an additional channel, HDMI Ethernet Channel, dedicated to Ethernet networking.
- Standard HDMI Cable. This cable is designed to support older consumer applications and has mostly been replaced by High Speed HDMI Cables. While it works well with some applications, it does not support the higher resolution, refresh rates and bandwidth requirements of most of the other applications on the market.
- Standard Automotive HDMI Cable. This is an older version of High-Speed Automotive HDMI Cables with special dust- and vibration-resistant HDMI type E connectors and a locking tab, as well as a stronger signal to support the automobile environment. It works with some applications but does not offer the advanced performance needed by most modern applications.
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