Gilles Karolyi is a German voice actor and dubbing artist known for his extensive work in animation, film, and video game localization. Based in Frankfurt am Main, he began his career as a narrator for the broadcaster 3sat in June 1996. His vocal quality is often described as confident and trustworthy, suitable for a wide range of characters. To refine his craft, he studied acting under Andreas Walther-Schroth in Frankfurt from 2001 to 2003 and spent time at the National Institute for Dramatic Art in Sydney in 2005. He is fluent in German, English, and French, and also has some knowledge of Hungarian.

Karolyi is a prominent figure in the German dubbing industry for anime and animated productions. He is widely recognized for voicing the character Heathcliff in the popular anime series Sword Art Online. His work also includes the role of Ignis Scientia in the CG-animated film Kingsglaive: Final Fantasy XV. Further demonstrating his range in animation, he voiced Velskud in Dragon Nest: Die Chroniken von Altera and Herr Hammer in the 2021 film The Ogglies.

Beyond animation, Karolyi has an extensive filmography in live-action dubbing, lending his voice to a diverse array of actors. He has frequently dubbed actors such as Billy Zane in films like Surviving Evil and Perfect Hideout, as well as Anthony Head, Jason Isaacs, and Dar Salim. His voice is also featured in numerous video games, documentaries, commercials, and audiobooks. While his role as Major Hanamura in Haikara-San: Here Comes Miss Modern Part 1 is noted, comprehensive records of his voice work are not consistently available across all platforms.