CD:UK (CountDown:United Kingdom), stylised as cd:uk, is a defunct music television programme which ran in the United Kingdom from 29 August 1998 until 1 April 2006. Originally run in conjunction with SMTV Live, the programme aired on ITV as a rival to the BBC's Live & Kicking and was the replacement for The Chart Show, which had been airing on the network for nine and a half years.

In contrast to its predecessor, which only showed promo videos, CD:UK was broadcast live on Saturday mornings with a studio audience and featured live performances, as well as star interviews and competitions. It also featured the Saturday Chart, which although was unofficial, usually reflected the new chart positions a day before the official chart was announced on Radio 1. This made the BBC's long-running Top of the Pops, which aired only the night before, seem very out-of-date broadcasting the previous week's chart. CD:UK later utilised an interactive chart based on viewers' votes, called the MiTracks Countdown. The show was sponsored by Tizer from 1999 until 2003, then Ribena from 2003 until 2005, and finally Rimmel from 2005 until its demise.

In 2002, the programme was criticised for showing "raunchy" performances in a slot aimed at children, sparked by a performance of "Dirrty" by Christina Aguilera. In response, a spin-off programme entitled CD:UK Hotshots, featuring music videos which could be considered unsuitable for daytime viewing, was launched in January 2003 and broadcast overnight.