Browning was born in Melbourne, Australia to Shelley and Andrew Browning. She has two younger brothers: Nicholas (born 1995) and Matthew (born 1997), and has a dog named Roxy and a cat named Jasper. Browning learned to speak with an American accent as a young child from watching Sesame Street.

Browning's acting breakthrough began when she was noticed by a friend's father at a school play; he recommended that she pursue acting as a profession. Shortly afterwards, Emily won an audition for a part in the Hallmark TV movie, The Echo of Thunder, alongside Judy Davis. Other parts in Australian productions followed, including a role in The Man Who Sued God, playing the daughter of Billy Connolly's character (she again co-starred with Connolly in Lemony Snicket's A Series of Unfortunate Events).

Emily's first major role was as Hayley Fulton, a troubled teen in Blue Heelers, who was taken in by Tess Gallagher (Caroline Craig). Browning appeared regularly from 2000 to 2002, when her character was forced to return to her birth family. She then starred in the horror film Darkness Falls, and also appeared alongside Orlando Bloom and Heath Ledger in the 2003 film Ned Kelly.

Emily's most recent, and highest-profile project has been the film Lemony Snicket's A Series of Unfortunate Events, in which she played the role of Violet Baudelaire, a role which won her the 2005 Australian Film Institute Award for Best Actress (International). Browning appears alongside Jim Carrey and Meryl Streep.

Browning has been quoted as saying that she is taking a break from acting, and has returned to Australia to attend school.