List of The X Factor (Australian TV series) finalists
"The X Factor" is an Australian television reality music competition that first aired in 2005. As of 2015, there have been seven seasons; one on Network Ten and six on the Seven Network. The final round of the competition features a number of solo singers and vocal groups: nine for season one, twelve for seasons two, three, four, five and seven, and thirteen for season six. A total of 83 acts have reached the finals of their seasons. Season three winner Reece Mastin is the most successful contestant from the show , having attained two top-five albums and three number-one singles, with nine platinum and three gold certifications. During the first season, the contestants were split into three categories: 16-24s (soloists aged 16 to 24), Over 25s (soloists aged 25 and over) and Groups (including duos). Each category was mentored by Mark Holden, Kate Ceberano and John Reid. From season two onwards, the 16-24s category was split into separate male and female sections, making four categories in all: Boys, Girls, Over 25s and Groups. The judging panel was replaced by Guy Sebastian, Natalie Imbruglia, Ronan Keating and Kyle  Sandilands who is the additional fourth judge. In season three, Natalie Bassingthwaighte and Mel B joined the judging panel as replacements for Imbruglia and Sandilands. Dannii Minogue and Redfoo replaced Mel B and Sebastian in the fifth season. In season five, the Over 25s category was changed to Over 24s (soloists aged 24 and over), the Boys age and the Girls age was both changed to 14 to 23. In season six, the Over 24s category was changed back to Over 25s (soloists aged 25 and over), the Boys age and the Girls age was both changed back to 14  to 24. In Season 8, Boys (male soloists) and Girls (female soloists) has been defunct and making the 14-21s (soloists aged 14–21s) to come back, the Over 25s category was changed to Over 22s (soloists aged 22 and over). Sebastian returned in season seven along with Chris Isaak and James Blunt to replace Redfoo, Bassingthwaighte and Keating. Mel B returned in season eight along with Iggy Azalea and Adam Lambert to replace Minogue, Issak and Blunt. Contestants. Key: