On October 15, 2007, Cartoon Network launched its HD simulcast feed under the name "Cartoon Network HD".
2010–present (USA); 2011–2015 (Europe, United Kingdom, Ireland)
On September 30, 2017 in USA, Cartoon Network USA brought back the SD feed for SD viewers, and they discontinued the 16:9 letterboxing the HD feed. And however, Programming originally produced in 4:3 and October 1, 2017, began to revive the HD symbol on its screen-bug, this marks the return of the SD feed of the network.
Beginning the week of July 17, 2015, Cartoon Network in Europe, United Kingdom, Ireland removed the HD symbol from its screen-bug. Then in 2 weeks later, on July 28, 2015 they discontinued the 4:3 feed and began letterboxing the HD feed for SD viewers. Programming originally produced in 4:3, however, remains stretched to 16:9.