Frank Welker

Frank Welker is an American voice actor, specializing in animal and other creature vocal effects. Welker has been involved in many 1980's and 1990's cult cartoons, including Doctor Claw from Inspector Gadget, Slimer on The Real Ghostbusters, and last, but not least, Megatron and Soundwave on The Transformers (which he would later reprise for Transformers: Prime). He was also Abu from Aladdin, Fall Apart Rabbit on Bonkers, and Nibbler in Futurama. Since the 2000's, he has been the voice of Garfield the cat and Curious George.

Scooby-Doo, Where Are You!
Grouped under "Voices".

Laff-a-Lympics

 * Dynomutt

Scooby-Doo on Zombie Island
This is the first Scooby-Doo to recognise Welker as the voice of Fred.

Scooby-Doo! Mystery of the Fun Park Phantom
This is a PC game.

Scooby-Doo and the Cyber Chase (video game)
This is a console video game.

Scooby-Doo! Night of 100 Frights
This is a console video game.

Scooby-Doo (film)
This role was for CGI characters in a live-action film. He shared the role with Jess Harnell.

What's New, Scooby-Doo?
As Welker and Casey Kasem are the only two to reprise the roles they originated, they are included in the opening credits. Therefore, any additional roles are uncredited.

Scooby-Doo! Mystery Mayhem
This is a console video game.

Scooby-Doo! Unmasked
This is a console video game.

Scooby-Doo! Who's Watching Who?
This is a console video game.

Scooby-Doo! The Mystery Begins
This is for a CGI character in a live-action film.

Scooby-Doo! Abracadabra-Doo
This is the first DTV film to include Fred's surname.

Scooby-Doo! First Frights
This is a console video game.

Scooby-Doo! and the Spooky Swamp
This is a console video game.

Scooby-Doo! Curse of the Lake Monster
This is for a CGI character in a live-action film.

Scooby-Doo! Adventures: The Mystery Map
This is a puppet film.

State Farm commercials
Uncredited.

Stoopid Buddy Stoodios's LEGO stop motion shorts
These are animated shorts, using real LEGO Scooby-Doo! minigures; uncredited.

Be Cool, Scooby-Doo!
This is the first series to credit Fred's surname.

Scooby-Doo in other media
Laff-a-Lympics was a show highlighted by Scooby-Doo('s involvement), so that doesn't count.

Johnny Bravo
Although not an official Scooby-Doo production, this is the first time Welker is recognised as the voice of Fred.

Notes/trivia

 * He's also appeared on-screen, with none other than Elvis Presley in the film, The Trouble with Girls, which also starred Nicole Jaffe.
 * Fred's interest in Elvis in What's New, Scooby-Doo?, may be an allusion to that.