Elizabeth Shaila Koshy (born March 31, 1996) is an American actress, television host, comedian and YouTuber. She began her career on Vine in 2013, before starting a YouTube channel.

Among her acting roles have been Aday Walker in Tyler Perry's horror comedy film Boo! A Madea Halloween (2016) and The Explorer in the YouTube Premium series Escape the Night (2017). She starred as Violet Adams in the Hulu drama television series Freakish (2016–2017). From 2017 to 2018, she was a contributor to the MTV television series Total Request Live. Since 2018, Koshy has produced and starred as the title character in the YouTube Premium comedy series Liza on Demand. From 2018 to 2019, she hosted the Nickelodeon game show revival Double Dare, for which she received an Emmy Award nomination. In 2020, she starred in the Netflix dance-comedy film Work It.

Koshy's main YouTube channel has amassed more than 17 million subscribers, and her two channels have a total of more than 2.5 billion combined views. She has received four Streamy Awards, four Teen Choice Awards, and a Kids' Choice Award. She was included in the 2019 Forbes 30 Under 30 Hollywood & Entertainment list and the Time 2019 list of the 25 Most Influential People on the Internet and its 2019 100 Next list.