As may be expected of a show that's run thirty-five seasons over fifty years, there are ''lots'' of characters here.

'''Note that almost all spoilers on the subpages up to and including Series 9 have been unmarked, and even images on some pages contain spoilers'''.

These are for the main TV series (''Series/DoctorWho'', obviously):
* The Doctor
** [[Characters/DoctorWhoDoctors General tropes]]
** [[Characters/DoctorWhoClassicSeriesDoctors Classic Series Doctors]][[note]]First Doctor, Second Doctor, Third Doctor, Fourth Doctor, Fifth Doctor, Sixth Doctor, Seventh Doctor, Eighth Doctor[[/note]]
** [[Characters/DoctorWhoRevivalSeriesDoctorsNineAndTen The Ninth and Tenth Doctors (2005–2010)]]
** [[Characters/DoctorWhoRevivalSeriesDoctorsElevenTwelveAndWar The Eleventh, Twelfth and War Doctors (2010–present)]]
* [[Characters/DoctorWhoCompanionsAndSupportingCast Companions and Supporting Cast]][[note]]The TARDIS[[/note]]
** [[Characters/DoctorWhoClassicSeriesCompanions Classic Series Companions]][[note]]Susan Foreman, Barbara Wright, Ian Chesterton, Vicki, Steven Taylor, Katarina, Sara Kingdom, Dorothea "Dodo" Chaplet, Ben Jackson, Polly, Jamie [=McCrimmon=], Victoria Waterfield, Zoe Heriot, Dr. Elizabeth "Liz" Shaw, Josephine "Jo" Grant, Sarah Jane Smith, Harry Sullivan, Leela of the Sevateem, K-9, Romana, Adric, Nyssa of Traken, Tegan Jovanka, Vislor Turlough, Kamelion, Perpugilliam "Peri" Brown, Melanie "Mel" Jane Bush, Dorothy "Ace" Gale [=McShane=], Dr. Grace Holloway[[/note]]
** [[Characters/DoctorWhoRevivalSeriesCompanions Revival Series Companions]][[note]]Rose Tyler, Mickey Smith, Adam Mitchell, Jack Harkness, Donna Noble, Martha Jones, Astrid Peth, Wilfred Mott, The Next Doctor, Rosita Farisi, Lady Christina de Souza, Adelaide Brooke, Amy Pond, Rory Williams, Craig Owens, Clara Oswald, Bill, Nardole[[/note]]
*** [[Characters/DoctorWhoRevivalSeriesCompanionsClaraOswald Clara Oswald]]
** [[Characters/DoctorWhoOtherSupportingCast Other Supporting Cast]][[note]]Queen Elizabeth I, Bret Vyon, Alpha, Beta and Omega, Professor Edward Travers, Alpha Centauri, Jago and Litefoot, The White Guardian, The Watcher, Richard Mace, Sabalom Glitz, Chang Lee, Jackie Tyler, Harriet Jones, Prime Minister, Pete Tyler, Sylvia Noble, The Jones family, Jenny, River Song, The "Meta-Crisis" Tenth Doctor, Dorium Maldovar, Canton Everett Delaware III, Madame Vastra, Jenny Flint, Strax, The Teselecta, Madge Arwell, Brian Williams, Angie and Artie Maitland, Cass, Ohila, The Moment, "The Curator", Handles, Tasha Lem, Danny Pink, Courtney Woods, "Rusty", Rigsy, Santa Claus, Ashildr[[/note]]
** [[Characters/DoctorWhoUNITStaff Doctor Who UNIT Staff]] [[note]]The Brigadier, John Benton, Mike Yates, Kate Stewart, Osgood[[/note]]
* [[Characters/DoctorWhoVillains Villains]][[note]]The Monk, Mavic Chen, The Celestial Toymaker, The Great Intelligence, The War Chief, Chancellor Goth, Nestene Consciousness, Omega, Davros, Sutekh, Morbius, Borusa, Magnus Greel, Black Guardian, Cyber-Leader, The Mara, Rassilon, Commander Gustave Lytton, Sil, The Rani, The Valeyard, The Kandyman, Fenric, Cassandra O'Brien.Δ 17, The Beast, Cult of Skaro, Lucy Saxon, The Dream Lord, Madame Kovarian, Mr. Clever, Half-Face Man, Gus, The Foretold, Seb, Colony Sarff, The Fisher King, Bonnie the Zygon[[/note]]
** [[Characters/DoctorWhoMasters The Master]][[note]]First Master, Thirteenth Master (Roger Delgado's Master), "Tremas" (Anthony Ainley's Master), "Bruce" (Eric Roberts's Master), "Professor Yana" (Derek Jacobi's Master), "Harold Saxon" (John Simm's Master), "Missy" (Michelle Gomez's Mistress)[[/note]]
* [[Characters/DoctorWhoAliensAndMonsters Aliens and Monsters]][[note]]Daleks, Thals, Zarbi, Drahvins, Cybermen, Macra, Ice Warriors, Quarks, Krotons, Time Lords, Autons, Homo Reptilia, Axons, Ogrons, Peladonians, Draconians, Sontarans, Wirrn, Zygons, Krynoid, Rutans, Movellans, Nimons, Trions, Eternals, Slitheen, Roboforms, Sycorax, Clockwork Droids, Cybus Cybermen, Ood, Judoon, Weeping Angels, Adipose, Vashta Nerada, The Silent Priests, Gangers, Tivolians, The Boneless, Dream Crabs[[/note]]

For the Franchise/{{Whoniverse}} spinoffs:
* Characters/BigFinishDoctorWho, comprising:
** Characters/BigFinishDoctorWhoDoctors
** Characters/BigFinishDoctorWhoCompanions
** Characters/BigFinishDoctorWhoVillains
** Characters/BigFinishDoctorWhoUNIT
** Characters/{{Gallifrey}}
* Characters/TheSarahJaneAdventures
* Characters/{{Torchwood}}
** Characters/TorchwoodMiracleDay

{{Expanded Universe}}ly speaking:
* Characters/BerniceSummerfield
* Characters/DoctorWhoMagazine
%% Characters/DoctorWhoMissingAdventures
* Characters/DoctorWhoNewAdventures
* Characters/DoctorWhoTheCurseOfFatalDeath
* Characters/EighthDoctorAdventures
* Characters/IrisWildthyme
* Characters/NewSeriesAdventures
* [[Characters/DrWhoFilms Peter Cushing films]]
* Characters/ScreamOfTheShalka
* Characters/DoctorWhoIDW
* Characters/DoctorWhoTitan
* [[Characters/DoctorWhoExpandedUniverse Other EU miscellany]]