[26] Chen worked with Kovar until age nine, and had begun taking lessons from Evgenia Chernyshyova, who was local to Salt Lake City and more easily accessible.

[47] Chen became eligible to compete in the ISU Junior Grand Prix in 2012–2013[41] and made his debut in Austria, where he won the title with the combined total score of 222.00 with 37 points to spare.

[74] Chen placed fourth overall and returned to California to work with Rafael Arutyunyan before the NHK Trophy,[71] where he finished second behind Olympic champion Yuzuru Hanyu.

Chen's placement, combined with his teammate Jason Brown's seventh-place finish, ensured Team USA would be able to send three men to the 2018 Winter Olympics.

Working with choreographers Shae-Lynn Bourne and Lori Nichol, he debuted a short-program set to "Nemesis" and a free skate with music from Mao's Last Dancer.

[89][90] After placing first in the short program and second in the free skate at 2017 Rostelecom Cup, Chen defeated Yuzuru Hanyu to win his first Grand Prix title.

[93][94] At the 2018 U.S. Championships, which served as trials for the Olympics, Chen performed seven clean quadruple jumps—two in the short program and five in the free skate—to win his second consecutive national title.

[96] At the 2018 Winter Olympics in Pyeongchang, South Korea, Chen performed his short program in the team event poorly and placed fourth,[97] but won bronze alongside his teammates.

His margin of victory over silver medalist Shoma Uno (47.63 points) was the greatest at a World Championships, Olympic Winter Games, and Grand Prix Final under the historical ISU Judging System (IJS).

[106] Chen's first competition as a full-time college student was the Japan Open, where he skated alongside Jeremy Abbott, Bradie Tennell, and Mariah Bell.

[110] At the 2018 Internationaux de France, Chen fell on his quadruple flip in the short program and entered the free skate in third place behind Jason Brown.

[127] He went on to set new highest scores of 224.92 in the free skate and 335.30 in the combined total, breaking his own world records in both segments, winning the title with 43.87 points over Hanyu.

[132] With the pandemic ongoing, skaters were largely assigned to the 2020–2021 Grand Prix based on geographic location; Chen was set to compete at Skate America.

[19] Chen recovered a week later at 2021 Skate Canada International, where he won both segments to win the competition with a 47.63-point margin over silver medalist Jason Brown.

[note 2] In June 2019, Chen was cast in Yuna Kim's show All That Skate, which took place at the Olympic Park KSPO Dome in Seoul, South Korea, and was directed by Canadian choreographers Sandra Bezic and David Wilson.

[183] In August 2023, Chen coached at Javier Fernandez's annual summer camp in Spain with Brian Orser, Tracy Wilson, and Florent Amodio.

[191][192] According to Forbes, Chen had long-term contracts with 11 partners: Bridgestone, Panasonic, Comcast, Nike, Toyota, Visa, OMEGA,[193] Coca-Cola, United Airlines and Kellogg's;[194] he has also worked with Powerade[195] and consumer brands Grubhub, Airweave, and Invisalign.

[196][197][198] Chen was featured on cornflakes boxes from Kellogg's, in Nike and Coca-Cola ads on billboards in New York City,[199][200] and inspired a United Airlines Olympic athlete super hero action figure.

[201] He starred in crossover television commercials for the 2022 film Jurassic World: Dominion with fellow Olympians Shaun White and Mikaela Shiffrin,[202] and promotional pieces and content for other sponsors.

[203][204] Chen is a brand ambassador for Panasonic and fronted their "Green Impact" initiative with tennis player Naomi Osaka and Olympic swimmer Michael Phelps.

[215][216] On social media, Chen promoted Uniqlo's Heattech collection,[217] products from Ultraslide,[218] and ramen from Japanese food and beverage company Maruchan.

[226] Chen's memoir One Jump at a Time: My Story was released in English by HarperCollins in November 2022, in Japanese by Kadokawa in late March 2023,[227] and in Russian by AST in October 2024.

[228] In it, Chen discusses his figure-skating career from his childhood as the youngest son of Chinese-American immigrants to his success, his family's determination to fund expensive training, his hip injury and subsequent surgery in 2016, and his disappointment at the 2018 Winter Olympics.

[257] Chen also reunited with all four of his siblings to compete on the Steve Harvey-hosted game show Celebrity Family Feud against Marvel's Shang-Chi actor Simu Liu's team.

Since 2017, he has been involved with Figure Skating in Harlem, a non-profit organization aiming to help girls of color grow in confidence, leadership skills, and academic achievement.

"[269] In early 2022, Chen partnered with the United States Department of Health and Human Services to aid in their public education initiative "We Can Do This", a campaign to promote COVID-19 vaccines,[270] and he spoke to immunologist and former National Institute of Allergy and Infectious Diseases (NIAID) director Anthony Fauci.

[272] In 2023, Chen joined the Elton John AIDS Foundation's social-media awareness campaign called InnerElton, an initiative protesting against LGBTQIA+ stigma and championing equality, health equity, and love.

After his sophomore year, Chen took a leave of absence to prepare for the 2022 Winter Olympics but returned in late 2022 to complete his baccalaureate degree in statistics and data science.

[293] He graduated from Yale in May 2024[294] where he won a Statistics and Data Science Outstanding Thesis Award for his senior project entitled "Utilizing Deep Learning to Predict Somatic Variant Pathogenicity.

[289] He is serving as an Ambassador for Public Outreach for the American Junior Investigators Association (AJIA),[296] an initiative established in 2024 to advocate for physician-scientists in the early stages of their careers.