UHD stands for Ultra High Definition, a video resolution category that is higher than standard HD (1080p). In most consumer contexts, UHD means 4K UHD, which is 3840 × 2160 pixels, or four times as many pixels as 1920 × 1080. You will see UHD used on TVs, streaming services, and physical media packaging as a shorthand for “this is the 4K version.” People often say “4K” and “UHD” interchangeably.
You will also see UHD in the format name Ultra HD Blu-ray, which is the disc standard for 4K releases. A UHD Blu-ray typically delivers a 2160p image and may include HDR (High Dynamic Range), which can improve highlights, shadow detail, and color depending on the transfer and your display. For example, a movie might be available as Blu-ray (1080p) and as Ultra HD Blu-ray (UHD, 2160p), with the UHD edition sometimes offering HDR10 or Dolby Vision in addition to the resolution bump. One small technical note: “4K” in cinemas often refers to a slightly different resolution (4096 × 2160), but for home releases and TVs, UHD almost always means 3840 × 2160.
