Aki Toyosaki is a Japanese voice actress and singer born on October 28, 1986, in Tokushima Prefecture, Japan. She is affiliated with the talent agency Music Ray'n.

Toyosaki's path to voice acting began in her high school years when she participated in local television programs in Tokushima. Receiving positive feedback from viewers about her voice inspired her to pursue a career where she could connect with people through sound. She later graduated from the Junior College Department of Osaka University of Arts. In 2005 and 2006, she successfully auditioned for Music Ray'n, launching her professional career. Her first major role came in 2007 as Amuro Ninagawa in the anime series Kenko Zenrakei Suieibu Umisho.

Her career reached a significant milestone in 2009 when she was cast as the protagonist Yui Hirasawa in the immensely popular anime K-On!. This role brought her widespread recognition and became one of her most iconic performances. That same year, she formed the voice actor unit Sphere with fellow Music Ray'n artists Minako Kotobushi, Haruka Tomatsu, and Ayahi Takagaki, embarking on a successful music career alongside her voice work. She also debuted as a solo singer in October 2009.

Toyosaki's talent has been recognized with numerous awards. At the 4th Seiyu Awards in 2010, she won the Best New Actress Award and, as part of the K-On! cast, the Best Musical Performance Award. The following year, at the 5th Seiyu Awards, she received two prestigious honors: the Best Lead Actress Award and the Best Personality Award.

Throughout her career, Toyosaki has portrayed a vast array of characters, demonstrating considerable range. She is known for her sweet voice and often plays roles ranging from young, cheerful girls to more mature women and even young boys. Among her many notable roles are several long-running or recurring characters. In the To Love-Ru series, she voices Momo Belia Deviluke. She is also the voice of Kazari Uiharu in the A Certain Scientific Railgun and A Certain Magical Index series. For fans of Laid-Back Camp, she plays Aoi Inuyama. In the Konosuba franchise, she voices the rival crimson magic user Yunyun. Her role as Isuzu Soma in the 2019 Fruits Basket reboot is another prominent example from the extensive list provided. Other well-known roles include Chiyuri Kurashima in Accel World, Homura in Dr. Stone, Marulk in Made in Abyss, and Lista in Cautious Hero: The Hero Is Overpowered but Overly Cautious.

Her career has continued strongly into the 2020s, with roles in series like Parallel World Pharmacy as Falma de Médicis, The Dangers in My Heart as Honoka Hara, and returning to voice Aoi Inuyama in the third season of Laid-Back Camp in 2024. In 2025, she was part of the cast for CITY The Animation.