Miss South Africa 2019

Tunzi began her pageantry career in 2017, when she was accepted as one of the top 26 semifinalists of Miss South Africa 2017.^[11] She returned to pageantry to compete in Miss South Africa 2019. On 26 June 2019, Tunzi was confirmed as one of the top 35 semifinalists of the competition, among initial applications.^[12] After further auditions, Tunzi was announced as one of the sixteen finalists on 11 July.^[7][13]

After being selected as one of the finalists, Tunzi went on to compete in the Miss South Africa 2019 pageant in Pretoria on 9 August.^[14] She progressed through the stages of the final, advancing to the top ten, then top five, and finally the top two until she was crowned the winner by predecessor Tamaryn Green, beating runner-up Sasha-Lee Olivier.^[15][16]

Following her win, Tunzi received prizes including R1 million, a new car, and a fully furnished apartment in the Sandton neighbourhood of Johannesburg, which is valued at R5 million, for her to use throughout her reign.^[17] The achievement allowed Tunzi to represent South Africa at the Miss Universe 2019 competition.^[16]

Miss Universe 2019

Tunzi arrived in Atlanta, Georgia for Miss Universe 2019 in November 2019.^[18] She competed in the preliminaries on 6 December, and competed in the finals on 8 December at Tyler Perry Studios. During the competition, Tunzi advanced to the top twenty as the first semifinalist for the Africa/Asia-Pacific continental region. She then advanced to the top ten, then the top five, and ultimately the final three. By the end of the event, Tunzi was crowned Miss Universe 2019 by outgoing titleholder Catriona Gray of the Philippines, beating first runner-up Madison Anderson of Puerto Rico and second runner-up Sofía Aragón of Mexico.^[19][20]

Tunzi's win is South Africa's third Miss Universe winner; she is the first black woman to win the Miss Universe title since Leila Lopes was crowned Miss Universe 2011, and the first to do so with afro-textured hair.^[21] With her win, 2019 became the first year that all four major United States-based pageants were won by black women; other titleholders were Nia Franklin (Miss America 2019), Kaliegh Garris (Miss Teen USA 2019), and Cheslie Kryst (Miss USA 2019).^[22] Additionally, 2019 would also become the first year that black women won the two most prestigious international pageants after Toni-Ann Singh of Jamaica later won Miss World 2019.^[23][24]

As Miss Universe, Tunzi lived in New York City, and took part in a number of events and appearances throughout the world.^[25] After winning Miss Universe, Tunzi was succeeded as Miss South Africa by her first runner-up Sasha-Lee Olivier.^[26]

In her capacity as Miss Universe, Tunzi traveled to Sumba^[27][28][29] and Jakarta in Indonesia,^{[30][31][32][33]} various cities within the United States^[34] and her home country of South Africa.^[35]

Due to the coronavirus pandemic, Tunzi became the longest reigning Miss Universe titleholder of 525 days (1 year, 5 months and 8 days), surpassing Lopes' reign of 464 days on 16 March 2021, and her reign came to an end on 16 May 2021, crowning Andrea Meza of Mexico as her successor in Seminole Hard Rock Hotel & Casino, Hollywood, Florida, United States.^[36]