"One of the Boys"
"I Kissed a Girl"
"Waking Up in Vegas"
"Thinking of You"
"Mannequin"
"Ur So Gay"
"Hot N Cold"
"If You Can Afford Me"
"Lost"
"Self Inflicted"
"I'm Still Breathing"
"Fingerprints"  

• "I Kissed a Girl"

The album's lead single, "I Kissed a Girl" was released in early May and soared up the charts. "I Kissed a Girl" was a commercial success. It topped the Billboard Hot 100 chart, becoming the 1000th chart-topper of the rock era. The song has since become a major worldwide hit, and along with the United States, it has topped the charts in more than 30 countries, including Australia, Canada, Ireland and the United Kingdom. It has sold over 3.4 million digital downloads in the U.S. as of May 2009.

• "Hot N Cold"

The second single, "Hot N Cold", made it onto the chart after the album came out due to digital downloads. It was released in early September, and peaked at number 3 on the US charts, making it Perry's second consecutive top 5 single. On November 14, the song became Perry's first number 1 on radio airplay. It is officially one of the ten best-selling digitally downloaded songs of all time. It has sold over 3.7 million digital downloads in the U.S. as of June 24, 2009.

• "Thinking of You"

"Thinking of You" was originally planned to be the first single from the album, but was scrapped for "I Kissed a Girl" due to its surge in popularity. "Thinking of You" received a video in late April 2008, but the video was removed from YouTube and replaced by a new video after the single was re-released as the third international single from the album. Perry shot the second video with director Melina Matsoukas in the first week of December 2008. The video for the single was released on December 23. The track peaked at #14 on the iTunes comprehensive chart and peaked at #29 on the Billboard Hot 100 on the week of February 12, 2009 where it remained for the next two weeks before declining to #31 in its seventh week on the chart. It has sold over 600,000 downloads in the U.S.

• "Waking Up in Vegas"

"Waking Up in Vegas" is the fourth official single release from the album; it went for adds on April 21st in the U.S. It was released to Australian radio on March 23, where it became the fourth most added song in its release week. The music video was shot by Joseph Kahn during March 2009 in Las Vegas. A forty second preview of it was posted on PerezHilton.com on April 10, 2009. It officially premiered on the iTunes store in the U.S. and Australia on April 28, 2009. It has sold over 754,000 digital downloads in the U.S. as of June 24, 2009.