"I Know" is a song by American R&B singer Dionne Farris. Written by Milton Davis and William DuVall, it was released in January 1995 as the first single from Farris' debut album, Wild Seed – Wild Flower (1994). The song was a hit in Farris's native United States, peaking at number four on the Billboard Hot 100 and spending 10 consecutive weeks at number one on the Billboard Top 40/Mainstream chart, becoming that ranking's most successful song of 1995.

Outside the US, "I Know" reached number one in Canada, where it was the 19th-most-successful single of the year. It also achieved top-40 placings in Australia, France, Iceland, New Zealand, and Scotland. It was nominated for the Grammy Award for Best Female Pop Vocal Performance in 1996.^[2] Davis and DuVall won an ASCAP Pop Award for writing the song in 1996.^[3]

Dave Sholin from the Gavin Report wrote, "A sensational talent has emerged from Arrested Development and her name is Dionne Farris. Kent Zimmerman [editor] ran up and down the hall screaming about this weeks ago and even recommended it to his A3 panel. Early airplay indicates Top 40 programmers agree."^[4] Charles Aaron from Spin felt the vocalist "relates her story of a too-late lover with carefully measured soul that reads Club VH-1. But the kick comes from a peek-a-boo slide guitar, weaving in and out of the nimble beats and subtle tambourine like a generational flare. It's as if Farris runs down the whole relationship scene for a front porch full of aunts and uncles and grandparents, all of whom nod in rhythm."^[5] Mike Joyce from The Washington Post described "I Know" as "a bluesy, slide guitar-riffed admonition".^[6]