List of Famous people born in Ontario, Canada

James Randi was a Canadian-American stage magician and scientific skeptic who extensively challenged paranormal and pseudoscientific claims. He was the co-founder of the Committee for Skeptical Inquiry (CSI), and founder of the James Randi Educational Foundation (JREF). Randi began his career as a magician under the stage name The Amazing Randi and later chose to devote most of his time to investigating paranormal, occult, and supernatural claims, which he collectively called "woo-woo". Randi retired from practicing magic at age 60, and from his foundation at 87.

Lilly Singh is a Canadian YouTuber, comedian, talk show host, and actress who formerly appeared under the pseudonym Superwoman, her long-time YouTube username. Born and raised in Scarborough, Toronto, Singh began making YouTube videos in 2010. By 2017, she was ranked tenth on the Forbes list of the world's highest paid YouTube stars, earning a reported $10.5 million; as of September 2019 she has fourteen million subscribers and over three billion video views. Singh has been featured in the annual YouTube Rewind every year since 2014. Forbes named her one of the 40 most powerful people in comedy in 2019. Singh has received an MTV Fandom Award, four Streamy Awards, two Teen Choice Awards, and a People's Choice Award.

Brian Clark is a Canadian businessman and survivor of the attacks on the World Trade Center on September 11, 2001. Clark worked for the American international brokerage firm Euro Brokers, which lost 61 employees that day, nearly one fifth of its New York branch.

Gladys Louise Smith, known professionally as Mary Pickford, was a Canadian-American film actress and producer with a career that spanned five decades. A pioneer in the American film industry, she co-founded Pickford–Fairbanks Studios and United Artists, and was one of the 36 founders of the Academy of Motion Picture Arts and Sciences.

Heather Menzies-Urich was a Canadian–American model and actress, known for her roles as Louisa von Trapp in the 1965 film The Sound of Music and Jessica 6 in the TV series Logan's Run.

Tyler Bertuzzi is a Canadian professional ice hockey forward currently playing for the Detroit Red Wings of the National Hockey League (NHL). Bertuzzi was drafted 58th overall by the Red Wings in the 2013 NHL Entry Draft.

Mae Martin is a Canadian comedian, actor and writer. Martin wrote and starred in the Netflix comedy Feel Good and has won two Canadian Comedy Awards as part of the comedy troupe "The Young and the Useless".

Thomas Charles Longboat was an Onondaga distance runner from the Six Nations Reserve near Brantford, Ontario and, for much of his career, the dominant long-distance runner. He was known as the "bulldog of Britannia" and was a soldier in the Canadian Expeditionary Force during the First World War.

Paul Kenneth Bernardo, also known as Paul Jason Teale, is a Canadian serial killer and serial rapist. Bernardo is known for initially committing a series of rapes in Scarborough, Ontario, a suburb of Toronto, between 1987 and 1990. He subsequently committed three murders with his then-wife Karla Homolka; among these victims was her young sister Tammy Homolka. After his capture and conviction, Bernardo was sentenced to life imprisonment and was later declared a dangerous offender unlikely to be released.

Penelope Oleksiak is a Canadian-American competitive swimmer who specializes in the freestyle and butterfly events. During the 2016 Summer Olympics, she became the first Canadian to win four medals in the same Summer Games and the country's youngest Olympic champion, with a gold in the 100 m freestyle, a silver in the 100 m butterfly, and two bronzes in the women's freestyle relays. With her gold medal win, she became the first athlete born in the 2000s to claim an Olympic gold medal in an individual event.