"Tattoo" received mixed to positive reviews from critics, who noted its similarities to Beyoncé's 2006 hit, "Irreplaceable", which was also co-written and produced by Stargate. The song peaked inside the top ten in the United States, Australia and Canada, and reached the top twenty in New Zealand and Germany. It has since been certified platinum in Australia and the United States. The song's music video premiered on Yahoo! Music on November 2, 2007. It was directed by Matthew Rolston and features a cameo appearance from sixth seasonAmerican Idol runner-up, Blake Lewis. A second music video for "Tattoo" was directed by Scott Speer and released only in European countries in September 2008, due to the song failing to make an impact on the singles charts there.
"Tattoo" was written by Amanda Ghost, Ian Dench and Norwegian production team StarGate, with the latter also producing the track. According to Sparks, she loved the song the first time she heard it and immediately wanted to record it. In an interview with Digital Spy, she spoke of the song saying:
"Tattoo's a song that can go so many different ways. Some people think of it as a break-up song, but, for me, it's about somebody who comes into your life and really touches you - be they a friend, a family member or someone you're in a relationship with. You know, with that kind of person, you can't just erase them from your memory if things go wrong. They're stuck there like a tattoo."
Sparks also described "Tattoo" as being very "Beyoncé-ish." The single was sent to U.S. Top 40/Mainstream radio on September 25, 2007. Prior to this, it was released for digital download in the United States, Australia and New Zealand on August 27, 2007. An extended play featuring additional remixes of the song, was made available for download in Australia and New Zealand on March 8, 2008. "Tattoo" was released in the United Kingdom in April 2008, but failed to impact the singles chart, where it peaked at number fifty. However, due to the commercial success of "No Air" there, her record company decided to re-release "Tattoo" in the United Kingdom on October 13, 2008 with a new music video.
"Tattoo" was a slightly greater success in Canada, where it reached number three on the Canadian Hot 100. In the United Kingdom, "Tattoo" debuted at number ninety on the UK Singles Chart on the week dated March 29, 2008. After weeks of ascending and descending the chart, the song reached its peak position of number twenty-four on November 1, 2008. In New Zealand, the song peaked at number twelve, where it spent a total of thirteen weeks on the chart.
The song's music video was directed by Matthew Rolston and premiered on Yahoo Music on November 2, 2007. In the video, a guy that Sparks likes begins following her, as she leads him to a merry go round. Sparks appears alone on the merry go round throughout the video. It also shows scenes of her and the guy on the merry go round having a good time. The video is shown in both color and black and white close face shots of Sparks intercut into it. It features a cameo appearance from Blake Lewis, the runner-up on the sixth season of American Idol, who appears briefly with Sparks on the merry go round at the end of the video.
A European version of the music video was directed by Scott Speer and was filmed to coincide with the song's re-release in Europe, due to the lack of interest of the original. The video was released in September 2008. It features Sparks in a room with several other people, at what appears to be a college gathering. As she begins to sing, Sparks is shown with a "love" tattoo on her upper arm, as vines draw themselves down her arm. Following this, the ink begins to appear on the others and the floors of the room, creating tattoos in the process. Some of the people in the room are couples, and the tattoos seem to bring them closer. The created tattoos depict images and words, such as a heart or the words "free" and "peace." Sparks is also shown by herself in an empty room, with a mirror covering the wall throughout. During one point, Sparks self-consciously looks in the mirror, coinciding with the song lyric "when I looked in the mirror, didn't deliver." There are also recurring shots of Sparks in another room against a green wall.