Solomon was born in the Sydney suburb of Vaucluse, New South Wales, Australia, and is Jewish.

[2][3][4][5] His local rabbi is Levi Wolff, a Chabadnik who runs Sydney Australia's largest Modern Orthodox Judaism congregation, Central Synagogue.

[6] His father, Michael, is a South African-born orthopedic surgeon, and his mother is Lucille Solomon.

[7] Solomon planned to follow his father into medicine after accepting an athletic scholarship in track at Stanford University.

[3] After breaking the 30-year-old national junior record in the 400m in 2011, Solomon was part of the Australian squad in the 4 × 400 metres relay at the 2011 World Championships in Athletics.

[3][9][6] At the 2012 IAAF World Junior Championships in Barcelona, Spain, he won a bronze medal in the 400m as he set a personal record of 45.52.

[14] Solomon competed for Australia again as captain of the junior soccer team at the 2013 Maccabiah Games.

[3] He was also named the top junior sprinter for 2013 at the NSW Athletics' awards, and the Maccabi Australia Outstanding Jewish Sportsman of the Year.

[3][9] Running indoors for Stanford, Solomon ran a 45.75 split in the 400 medley relay at the 2014 NCAA Indoor Track and Field Championships (as the Cardinal won the title in 9:37.63), and also won the Mountain Pacific Sports Federation (MPSF) title in the 400 in 46.24, and ran a 500 in 1:01.44 (the third-fastest time in the world to that point).

At age 26, he was an Australian Athletics Team co-captain,[25] stating at the end of 2019 that he was aiming to medal at the upcoming 2020 Tokyo Olympics.

He also competed in the 400m at the 2022 World Athletics Championships held in July at the Hayward Field in Eugene, USA but didn't advance from the heats.