In the United Kingdom the song spent two weeks at number one and is the 19th-best selling single of all time by a female artist, with over a million copies sold.

The video suggests that she is the only female in the world, echoing the song's title and lyrics, and critics praised its bright, colorful theme.

[2] In February 2011, Stargate said that Rihanna approached the Norwegian production duo before she began recording the then-untitled project, saying that she wanted to have fun and produce happy, uptempo songs.

[3] According to Tor Erik Hermansen of Stargate, "Only Girl (In the World)" was the first song created for Loud and Rihanna decided to include it on the album before recording her vocals.

[3] Furthermore, American singer Katy Perry expressed interest in recording "Only Girl (In the World)", but the song was specifically composed by Stargate for Rihanna.

The song was mixed by Phil Tan at the Ninja Beat Club in Atlanta and by Vee at The Bunker, with engineering by Damien Lewis.

[1] The cover of "Only Girl (In the World)" maintains the semi-nude aesthetic seen in Rated R but introduces a red color scheme, serving as a bridge between the two themes.

[8] On August 31, 2010, Rihanna posted an announcement on Twitter, tagging Ryan Seacrest's username, that she would release a special song that everyone could listen to repeatedly just like the only girl in this world in less than 10 days.

[16][17][18] Brad Wete of Entertainment Weekly described the song as a "stronger, sexier" version of her 2007 single, "Don't Stop the Music".

"[16] Fraser McAlpine of the BBC compared the song's message to that of the German fairy tale "Rapunzel"; Rihanna is not willing to throw her hair out of the castle for just any man to come and satisfy her, "particularly not someone who isn't prepared to make the climb up to her scarily high window.

Chloe Govan remarked that "Only Girl (In the World)" symbolizes Rihanna's newfound and bold personality, reflecting not only a shift in style but also in sound.

[24] MTV News writer James Dinh praised the uptempo song, comparing it to the "stark" lead single "Russian Roulette" from Rihanna's previous Rated R.[17] Monica Herrera wrote for Billboard that "Only Girl (In the World)" "aims squarely for dance-floor domination.

[21] According to Levine and Jim Farber of the New York Daily News, "Only Girl (In the World)" was Rihanna's most pop-sounding song since "Don't Stop the Music".

[21][25] Analyzing the song, the BBC's Fraser McAlpine questioned why "Only Girl (In the World)" leaves a "positive impression" on the listener despite its arrogant, domineering tone.

There is simply too much pressure being stuffed into our ears, with too much brutal force"), he concluded that Rihanna sings the song with great passion and gave it four stars out of five.

[22] James Dolan gave the song two-and-a-half stars out of five in Rolling Stone, writing that "the trance beat won't keep you in the club unless someone else is paying for the drinks.

[35][36] The song has been certified six times platinum by the Recording Industry Association of America (RIAA), and has sold 3.6 million copies in the US as of June 2015.

[50] Rihanna was the second non-United Kingdom, non-North American million-selling artist; the first was Danish singer Whigfield with her 1994 song, "Saturday Night".

[50] Although at the time the only other female two-song million-seller was Canadian singer Celine Dion, two of Rihanna's subsequent singles—"We Found Love" (2011) and "Diamonds" (2012)—have also sold more than a million copies each.

"[59] According to Joyce Lee of CBS, Rihanna appeared to have progressed from the "edgy" music videos of the Rated R singles to a more feminine, colourful tone.

[71] Two days later, Rihanna sang "Only Girl (In the World)" on the Italian version of The X Factor in a floral-print bikini, boots and a red pigtail.

[73] The singer returned to London on November 11 to record an interview for The Graham Norton Show, which included a live performance of "Only Girl (In the World)".

She began with an a cappella version of "Love the Way You Lie (Part II)", sitting on a stylized tree of lights above "a field of sable-colored blades of grass.

[75] Rihanna performed a short version of "Only Girl (In the World)" at the 31st Brit Awards on February 15, 2011,[76] as part of a medley with two other singles from Loud: "S&M" and "What's My Name?".

[77] She had planned to perform "S&M" only (to coincide with its United Kingdom release), but was asked by the British Phonographic Industry to "tone down the sexual references in the song's lyrics".

Katy Perry covered "Only Girl (In the World)" as part of an acoustic mash-up with Willow Smith's "Whip My Hair" on her California Dreams Tour (2011).