Ratatat first met as students at Skidmore College, but they did not work together until they recorded several songs under the name "Cherry" in 2001. Their 2004 debut, Ratatat, was written and recorded in Mast's Crown Heights, Brooklyn apartment on Stroud's PowerBook. The album is entirely instrumental with the exception of vocal excerpts at the beginning and end of selected tracks. The group debuted by releasing the single Seventeen Years on Evan and his brother's record label Audio Dregs in the US and Rex Records in the UK. Seventeen Years was released again on Evan and his brother E*Rock's record label Audio Dregs. They then signed for XL Recordings, releasing their debut album and the single Germany to Germany. Ratatat occasionally remixes others for collected release on Ratatat Remixes Vol. 1 (which garnered the attention of Rolling Stone), as well as the later second volume, both of which were self-released in co-operation with Audio Dregs.
Both musicians have had experience with other projects, such as Mast's E*vax and King Pang and Stroud's stage work with B4-4, Joe Satriani and Manowar. Stroud has also recorded with Ben Kweller on On My Way. Ratatat has toured with bands such as Björk, Daft Punk, Mouse on Mars, Interpol, Franz Ferdinand, CSS, The Faint, Super Furry Animals, Clinic, Panther and The Killers. In 2006 they supported Mogwai in Japan.
On October 6, 2006 Ratatat became the first band to perform a public show inside the Guggenheim Museum in New York City.
On October 10, 2006 a new demo album from Ratatat entitled 9 Beats was leaked online. This set of tracks does not appear on any official discography listings. The tracks consist of short instrumental electronic musical pieces and demos for their next mixtape. This release was followed by another remix album, Ratatat Remixes Vol 2..
It has been rumored that they will be signed by Star Trak as the understudies of the Neptunes.
Mast has most recently collaborated with former Shudder to Think vocalist Craig Wedren on a record for a Tokyo independent label, Mold Recordings and said to be finishing a follow up solo album for Audio Dregs.
From June 2007 until October 2008, Ratatat had Martin Bonventre accompany them on their European tour and Fall shows in America as the pianist/synthesizer player. He drew much attention due to his enormous afro and crazy, erratic dance movements on stage. The reason for his leaving the performance is unknown.
Ratatat's live performances bear strong similarities to the performances of the psychedelic rock bands out of San Francisco in the 60s, with energetic light shows, swirling colors projected onto a screen, and random clips of movies thrown in.