|Age|| 10 (dog years) (Clifford the Big Red Dog)
4 months (Clifford's Puppy Days)
|Friends||T-Bone, Cleo, Mac|
|Families||Emily Elizabeth Howard (owner)|
|First appearance||My Best Friend|
|Voiced by|| Brent Titcomb (1988 series)|
John Ritter (2000 series, Clifford's Really Big Movie)
Lara Jill Miller (Clifford's Puppy Days)
Frank Welker (PBS Kids "Ready to Learn" bumpers)
Clifford is a helpful, outgoing and a friendly dog. He will always help his buddies in their times of need and give them amazing advice. However, he can also can be gullible and naive and sometimes believes everything he is told.
Clifford is a very big red dog, which sometimes he gets into trouble because of his size or is tempted into trouble by his friends and those he meets. His size, like giants in medieval legends, is inconsistent—he is often shown as being about 25' tall from paws to head, but can appear far larger. Emily Elizabeth gave him a huge amount of love, which caused his big size. Clifford has a tag in Clifford's Really Big Movie.
- Although John Ritter died in 2003, his voice can be heard as Clifford as late as 2004 because Clifford's Really Big Movie was released posthumously.
- Clifford was given a prequel series Clifford's Puppy Days that took place during Clifford's puppyhood prior to the Howards' move to Birdwell Island. In this series Clifford is voiced by Lara Jill Miller.
- Clifford’s size is never directly explained. However in Clifford's Puppy Days that took place during Clifford's puppyhood it is implied that there was a titular event that cause the rapid and unholy growth of the creature.