As Mario is to Nintendo, Sonic is to Sega. Due to the number of characters there are, as well as how many tropes each of them have, the characters have been split into separate pages. It should be noted there are various continuities that exist within the series and each may have its own respective page for its cast. The following pages are only for tropes that are consistent across most of the continuities. Any tropes exclusive to that continuity belongs on the respective page.

Main Sega Continuity:

Games

• Main Characters^{Character List}Miles "Tails" Prower, Knuckles the Echidna, Amy Rose
  • Sonic the Hedgehog
• Recurring Characters^{Character List}Mighty the Armadillo, Ray the Flying Squirrel, Maria Robotnik, Team Chaotix (Vector the Crocodile, Espio the Chameleon, Charmy Bee), Cream the Rabbit, Big the Cat, Omochao, Emerl, Vanilla the Rabbit, Blaze the Cat, Silver the Hedgehog
  • Team Dark^{Character List}Shadow the Hedgehog, Rouge the Bat, E-123 Omega
• Eggman Empire^{Character List}Dr. Ivo "Eggman" Robotnik, Metal Sonic, Orbot and Cubot, Sage, Mecha Sonic, Eggrobo, Tails Doll, Metal Knuckles, Metal Tails, Metal Amy, The Prototypes, Hard Boiled Heavies, E-102 Gamma, E-100 Series, Egg Golem, Mecha Knuckles, Shadow Androids, SCR-HD, Badniks
  • Dr. Ivo "Eggman" Robotnik
• One-Shot Characters^{Character List}Robotnik's Mechanix, Bean the Dynamite, Bark the Polar Bear, Honey the Cat, Tikal, GUN Commander, Princess Elise the Third, The Duke of Soleanna, Chip, Professor Pickle, Custom Hero/Avatar, Titan Pilots, Master King, Lumina Flowlight, Illumina, Sharah, Marine the Raccoon, Caliburn, Dodon Pa, Mirage Express Employee, The Conductor, Ariem
• Classic Era Antagonists ^{Character List} Fang the Hunter, Trip the Sungazer, Black Dragon, Witchcart, Battle Kukku Army
• Modern Era Antagonists 1^{Character List}Chaos, Gerald Robotnik and the Biolizard, King Boom Boo, Black Doom, Void, Eggman Nega, Johnny, Captain Whisker, Solaris (Iblis & Mephiles), Erazor Djinn, King Arthur, Merlina, The Babylon Rogues
• Modern Era Antagonists 2^{Character List}Dark Gaia, Nega-Mother Wisp, Time Eater, Jackal Squad, The Deadly Six, Infinite, The Titans, THE END
• Other Groups and Species^{Character List}Flickies, Chao, Knuckles Clan, GUN, Boos, Black Arms, Wisps

Adaptations

Animated

• Sonic Prime

Comics

• Sonic the Hedgehog (IDW)
  • The Restoration
  • Eggman Empire
  • Clean Sweep Inc.
  • Independent Antagonists
  • Other Characters
  • Classic Era Characters

Various Continuities:

Animated

• Adventures of Sonic the Hedgehog
• Sonic the Hedgehog (SatAM)
• Sonic the Hedgehog: The Movie
• Sonic Underground
• Sonic X
  • Sonic's World
  • Human World
  • Metarex Saga Characters
• Sonic Boom
  • Team Sonic and Friends
  • Antagonists
  • Other Characters

Comic Books

• Sonic the Hedgehog (Archie Comics)
  • Freedom Fighters
  • Knuckles and the Chaotix
  • Team Dark
  • Time and Space Travelers
  • Other Allies
  • Other Allies (Old Universe)
  • Eggman Empire
  • Eggman Empire (Old Universe)
  • Other Antagonists
  • Other Antagonists (Old Universe)
  • Citizens of Mobotropolis
  • Other Characters
  • Worlds Collide
  • Worlds Unite
• Sonic the Comic

Characters By Index

• Sonic the Hedgehog
• Sonic the Hedgehog 2
• Sonic the Hedgehog CD
• Sonic 3 & Knuckles
• Sonic the Fighters
• Sonic Adventure
• Sonic Adventure 2
• Sonic Heroes
• Shadow the Hedgehog
• Sonic Storybook Series
• Sonic Chronicles
• Sonic Generations
• Sonic Lost World
• Sonic Mania
• Sonic Forces
• Sonic Frontiers
• Sonic Superstars

Live-Action

• Sonic the Hedgehog (film series)
  • Extraterrestrials
  • Humans

Others

• Other Comics and Cartoons

Crossovers:

• Mario and Sonic at the Olympic Games^note Sonic, Tails, Knuckles, Amy, Dr. Eggman, Shadow, Vector, Blaze, Silver, Metal Sonic, Rouge, Cream, E-123 Omega, Espio, Jet, Eggman Nega, Zavok, Zazz, Wave, Sticks, Charmy, Chao, Orbot and Cubot
• Super Smash Bros.
  • Super Smash Bros. Brawl - 32 to 39^note Sonic
  • Super Smash Bros. - Assist Trophies^note Shadow the Hedgehog, Knuckles the Echidna
  • Super Smash Bros. - Enemies^note Eggrobo
  • Super Smash Bros. - Others^note Miles "Tails" Prower, Silver the Hedgehog
• Wreck-It Ralph: Cameo Characters^note Dr. Eggman, Sonic the Hedgehog, Tapper's Portraits (Tails)
• LEGO Dimensions
  • LEGO Dimensions Year Two^note Sonic the Hedgehog, Dr. Eggman, Miles "Tails" Prower, Knuckles the Echidna, Amy Rose, Shadow the Hedgehog, Big the Cat, Robo Sonic, Mecha Sonic, Metal Sonic, Chaos, Omochao
• Puyo Puyo Tetris^note Sonic the Hedgehog