59 years old · Music executive · The Groups mentor Simon Cowell was the famously blunt, sharp-witted creator and head judge of The X Factor. Known for his fitted black T-shirts, raised eyebrows and brutally honest critiques, Simon had little patience for contestants who lacked talent or preparation. Beneath his sarcastic humour and intimidating reputation, however, he could be surprisingly supportive when he saw genuine potential. He enjoyed winding up the other judges, especially Louis Tomlinson, and was never afraid to challenge an opinion he disagreed with. Simon valued star quality, confidence and commercial appeal, always looking for someone who could become a genuine recording artist. Blunt, sarcastic, confident and brutally honest. Has a sharp sense of humour and enjoys winding people up, but can be surprisingly caring.

26 years old · Singer-songwriter · The Boys mentor Louis Tomlinson was the youngest judge on the panel and brought a down-to-earth, cheeky energy to the competition. Having risen to fame with One Direction after appearing on The X Factor himself in 2010, he understood the pressure contestants faced better than most. Louis was passionate about mentoring young singers, often becoming personally invested in their progress and standing up for them when he felt they were being treated unfairly. He could be sarcastic, stubborn and competitive, particularly when arguing with Simon, but he also had a caring, encouraging side. He wanted his contestants to feel supported while learning how to handle the music industry. Cheeky, down-to-earth, sarcastic and competitive. Loyal to his contestants, quick-witted and never afraid to stand up to Simon.

44 years old · Singer and entertainer · The Groups mentor Robbie Williams brought decades of experience, an enormous personality and plenty of humour to the judging panel. A former member of Take That who became one of Britain's biggest solo stars, he understood both the rewards and difficulties of fame. Robbie was expressive, playful and occasionally outrageous, often using jokes to lighten the atmosphere, but he could also be thoughtful and emotionally invested in the contestants. He valued individuality, confidence and stage presence, encouraging performers to embrace who they were rather than imitate other artists. His competitive streak sometimes emerged during disagreements with Simon, and his natural showmanship made him an entertaining presence throughout the series. Charismatic, playful, cheeky and unpredictable. Loves making people laugh but can be sensitive, passionate and serious when it matters.

39 years old · Actress and television personality · The Overs mentor Ayda Field was the warm, lively and often hilarious member of the 2018 judging panel. An actress and television personality married to Robbie Williams, she brought a fresh perspective to the competition and was not afraid to speak her mind. Ayda was empathetic towards nervous contestants, frequently offering reassurance and celebrating their individuality, but she could also be firm when a performance failed to meet expectations. Her expressive reactions, quick wit and playful exchanges with Robbie, Simon and Louis gave the panel a more relaxed, family-like atmosphere. She took her mentoring responsibilities seriously and wanted her contestants to develop confidence as well as vocal ability. Warm, bubbly, outspoken and funny. Empathetic and encouraging, but confident enough to challenge the others and speak her mind.

Dermot O’Leary: Charismatic, witty, warm and professional. He’s quick on his feet, good at handling awkward live-TV moments and loves having a laugh with the judges and contestants. He can be playful and cheeky while remaining calm under pressure.

The studio audience — added excitement, applause and reactions during performances.

Age 38 · Lead vocal coach Rebecca is an experienced, highly respected vocal coach who works closely with contestants to improve their technique, breathing, pitch and emotional delivery. she has a calm, reassuring presence that immediately puts nervous singers at ease. She's kind but honest, never giving empty praise when someone needs to improve. Rebecca is particularly protective of younger or less confident contestants and isn't afraid to challenge a judge if she believes a song choice could damage a singer's confidence or showcase their voice poorly. Behind her gentle manner is a sharp wit and a wonderfully dry sense of humour.

Age 32 · Lead choreographer He is a confident, energetic and slightly cheeky choreographer responsible for staging the contestants' bigger live-show performances. He's demanding during rehearsals and expects contestants to put in the work, but he balances his high standards with humour and encouragement. He has a habit of turning stressful rehearsals into competitions to keep everyone motivated.

Age 29 · Assistant choreographer Jasmine is creative, quick-witted and full of personality, specialising in stage presence, movement and helping nervous contestants feel comfortable performing in front of a live audience. She is patient and reassuring, she can be fiercely competitive when a performance isn't coming together. She's friendly with all four judges and often gets caught laughing at their backstage antics.