"Day 1" (also titled "Dia 1") is a song recorded by American singer Leslie Grace. It was released as the second single from her self-titled debut studio album Leslie Grace (2013) on November 19, 2012, through Top Stop Music. The song is in the bachata genre and has a length of 3 minutes and 11 seconds. It was written by Leslie Grace, Israel Mercedes, and Jason Rivera.
The music video, released in early February 2013, features Leslie Grace singing into a camera in a studio setting. The video concludes with her saying, "You've had me from day one." Two versions of the song exist: a primarily Spanish version and a version with more English lyrics.
"Day 1" was recognized by ASCAP in 2014 as among the most successful tropical songs. Commercially, it reached number 21 on the US Billboard Hot Latin Songs chart, number 22 on the US Latin Airplay chart, and peaked at number 1 on the US Tropical Airplay chart. On the year-end Hot Latin Songs chart for 2013, it ranked at number 89.
Other notable songs titled "Day 1":
- "Day 1" by HONNE – A 2018 song from the album Love Me / Love Me Not. The lyrics focus on loyalty and being with someone from the very beginning ("You'll always be my day one / Day zero when I was no one").
- "Day 1" by Red Velvet – A Korean-language song that is the ninth track on the group's first studio album The Red (2015). It has been described as combining bass and piano with the sweet vocals of the group members.
