Birth Chart and Horoscope of April 21 births
- Abel Cullum
- Alaa' Al-Shaqran
- Aleh Slautin
- Alex Martin (racing driver)
- Alexis Gray-Lawson
- Allan Hansen
- Amer Al-Fadhel
- Anastasia Prikhodko
- Andrade (footballer, born 1957)
- Andy Mitchell (politician)
- Artyom Varakin
- Ángel Daniel Vassallo
- Ángel Faretta
- Beatriz Recari
- Bill Faul
- Bill Ingle
- Billy Konstantinidis
- Blair Cowan (rugby union)
- Bob Eaton (diver)
- Bob Varsha
- Bobby Hutton
- Bonnafet Tarbouriech
- Brent Morel
- Bruce Duperouzel
- Brutus Beefcake
- Carla Mancini
- Carlos César Neves
- Carmen Barbieri
- Carmen Forest
- Charlie Hoffman
- Charlotte Bredahl
- Chelo Vivares
- Chris Harms
- Chris Neufeld
- Cindy LaCrosse
- Claudie Minor
- Clayton Pachal
- Cliff Calvert
- Cristian S. Calude
- Cynthia Kirchner
- Cyril Pahinui
- Dale Eggeling
- Dale Patchett
- Dan Skuta
- Dave Meyers (basketball)
- Dave Ryan (rugby union)
- David Carter (tennis)
- David J. Porter
- David M. O'Connell
- David Mallett
- David Twohill
- David Van Tieghem
- Deborah Ahenkorah
- Dipankar Chatterji
- Doc Holliday (American football)
- Dom Starsia
- Doug Soetaert
- Duke Fergerson
- Ebiet G. Ade
- Edwin Chalar
- Eleanor Joanne Daley
- Emre Batur
- Eric Devendorf
- Erick Mombaerts
- Eva Nordung Byström
- Fauzzi Kassim
- Forrest (singer)
- Fátima Felgueiras
- Gabriel Loire
- Gabriela Isler
- Gary Beecham
- Gerald Early
- Gerardo Aranda Orozco
- Girishwar Misra
- Glenn Hansen
- Go Seul-ki
- Greg Harts
- Han Xu (footballer)
- Hans Verèl
- Iggy Pop
- JR Buensuceso
- Jamal Ehsani
- Jan Adams (surgeon)
- Janet Zarish
- Jean Piché
- Jeff Fehring
- Jencarlos Canela
- Jim Lee (broadcaster)
- Jim March
- Jim Roers
- Jo Nymo Matland
- Joe Jopling
- John Brumby
- John Vella
- John Walker (film producer)
- John Wolfe Jr.
- Josh Mantellato
- José Fábio Santos de Oliveira
- João Guilherme
- Julio César García
- Julius Caesar Herrera
- Justin Carter
- Jürgen Bertow
- Jürgen Blum
- Karlen Asieshvili
- Kevin Graham
- Kielo Tommila
- Kit Vaughan
- Kyle Helms
- Larry Schweikart
- Laura Podestà
- Leandro Martínez Montagnoli
- Leonard Warren
- Leroy George
- Lourdes Figueroa
- Lucky Oceans
- Majd Eddin Ghazal
- Mark Lofthouse
- Mark Olberding
- María del Mar Jover
- Max O. Cogburn Jr.
- Maximiliano Cerato
- Mehmood-ur-Rasheed
- Michael Conahan
- Michael Duhig
- Michael Freedman
- Miguel Roca
- Mike Clasper
- Mirko Valdifiori
- Monica Havelka
- Monica Hickmann Alves
- Mpho Tshivhase
- Nadif Chowdhury
- Nazeem Hussain
- Nina Temple
- Néko Hnepeune
- Nílton Ferreira Junior
- Panagiotis Zorbas
- Park Jung-hae
- Patrick Ottmann
- Paul Dyster
- Paulo Hartung
- Peter G. Sheridan
- Peter Guy Wolynes
- Peter Kosminsky
- Peter Millar (footballer)
- Peter O'Donnell
- Phil De Fries
- Philippe Guerdat
- Phillip Omondi
- Pietro Gandolfi
- Piotr Mowlik
- Préjuce Nakoulma
- Pádraig Horan
- Randy Sterling
- Raphael Thattil
- Reg Thomas (ice hockey)
- Rich Whitney
- Rick DeMont
- Ricky Berens
- Robert Grey (musician)
- Robert Rotenberg
- Rodney Stuckey
- Rollo May
- Rubén Arocha
- Ryan Kersten
- Ryan King
- Sanora Wong Howe
- Seyed Hossein Mirfakhar
- Sharifah Aryana
- Sharron Proulx-Turner
- Sidnei (Cape Verdean footballer)
- Sotirios Pastras
- Staf Van Eyken
- Stefanie Preissner
- Steve Vickers (ice hockey)
- Suman Dutta
- Susan Beschta
- Tahir Raj Bhasin
- Tawfik Khatib
- Tchô
- Teague Moriarty
- Terry Hu
- Thiago Cionek
- Thomas F. Proctor
- Tim Leiweke
- Tobias Willers
- Todd Phillips (musician)
- Toninho Cerezo
- Tony Romo
- Vicki Williams
- Viola Canales
- Vladimir Isaichev
- Vítor Melo Pereira
- Walter Zobell
- Will Daniels
- Win Myint (politician, born 1954)
- Wojciech Waglewski
- Yoichi Miyazawa
- Yuhan Tan