[7] Caillat took piano lessons as a child, but lacked significant inspiration until she turned 11 years old, when she became enthralled with Lauryn Hill's performance in Sister Act 2.

[8] She realized that she wanted to be a singer, and began taking vocal lessons, performing onstage for the first time in sixth grade.

Caillat soon met producer Mikal Blue, who hired her to sing on techno songs used at fashion shows.

"[11] The popularity of Caillat's MySpace profile led her to become the number-one unsigned singer in her genre for four consecutive months.

[12] Caillat's debut album, Coco, was released on July 10, 2007, in Australia and Asia and a week later in North America.

[17] The second single from Coco, "Realize", was released on January 23, 2008, peaking at number 20 on the Billboard Hot 100 chart, becoming her second Top 20 hit in the United States.

The fourth and final single from the album in the United States was, "Somethin' Special (Beijing Olympic Mix)", released on July 29, 2008.

It was released to give support to the American athletes participating in the 2008 Beijing Summer Olympics, in China, and also was included on the AT&T Team USA Soundtrack.

She is also featured in Colombian singer Juanes' album La vida... es un ratico (en vivo) in the song "Hoy Me Voy".

Caillat provided background vocals for and co-wrote Taylor Swift's song "Breathe", on her album, Fearless.

On January 13, 2009, Caillat also released a duet with Jason Mraz, called "Lucky", on his album, We Sing, We Dance, We Steal Things.

[22] Caillat had writer's block during the recording sessions, so she enlisted her friends Kara DioGuardi and Jason Reeves, and they went to Hawaii for three weeks, rented a beach house and wrote songs.

The "lilting" mid-tempo ballad "features an instantly catchy chorus and toe tapping melody," as defined by Melinda Newman of HitFix.

[26] It achieved chart success in the United States, reaching number twelve on the Billboard Hot 100, her second highest-charting single and her highest debut with 118,000 first-week downloads,[27] spending fourteen weeks at number two on the Adult Pop Songs and topping the Adult Contemporary chart.

In July 2010, Caillat performed "God Bless America" during the seventh inning stretch at the 2010 Major League Baseball All-Star Game.

[34][35] The set, largely produced by Greg Wells, features one guest appearance by rapper/actor Common, who graces "Favorite Song", while her songwriting collaborators include Ryan Tedder, Toby Gad, Jason Reeves and Rick Nowels.

[41] The song "What If" debuted at number 77 on the Billboard Hot 100, due to strong digital downloads on the week of the album release.

[43] Fans chose the next single of the album via an online poll on Caillat's website, with "Favorite Song" receiving the most votes.

[45][46] Caillat appeared in the third episode of the cancelled NBC television series The Playboy Club as 1960s singer Lesley Gore.

The album features collaborations with Brad Paisley, Gavin DeGraw, Justin Young and Jason Reeves.

Caillat sang the national anthem at the 3rd game of the 2013 World Series between the Boston Red Sox and the St. Louis Cardinals on October 26, 2013.

A lyric video was released June 10, 2014, featuring fans, as well as female celebrities such as Hoda Kotb, Miranda Lambert, Sara Bareilles, Katharine McPhee and the members of Fifth Harmony without makeup.

[62] During 2018, Caillat formed a band called Gone West with her fiancé Justin Young, longtime collaborator Jason Reeves, and his wife Nelly Joy.

[72] In September 2021, Caillat released a cover of the song, "White Christmas", which was a collaboration with country singer Brett Young.

[73] In December of that year, Caillat made an appearance on CMT Crossroads Christmas to perform her duet with Young.

[86] Jill Renae Hicks of the Columbia Daily Tribune describer her music as "sunny", frequently characterized by "beachy, ray-soaked tunes filled with bouncy guitars and upbeat percussion ... fronted by the singer’s California-drawl alto".

[87] Reuters found her style to be reminiscent of female musicians from the late-1970s, namely Karla Bonoff and Nicolette Larson, and considers her timbre and tone to be similar to that of Sheryl Crow.

[88] She has experimented with genres such as rock, hip-hop, country, R&B, and dance music, particularly on her fifth studio album Gypsy Heart.

[88] Caillat has spoken about suffering from stage fright earlier in her career,[95][96][97] an experience she wrote about in her song "One Fine Line".

[100] Her song Worth it, released in 2023, is inspired by the relationship and break up In 2010, Caillat posed nude for the May issue of Allure magazine, alongside Emmanuelle Chriqui, Regina Hall, Kara DioGuardi, and Jessica Capshaw.