Real Name: Guk Chorok Nationality: South Korea Date of Birth: July 28, 2005 Position: Rapper, Lead Dancer Personality: Easygoing and full of energy, she leads the bright atmosphere within the team. Characteristics: She has the surname 'Guk,' which is very rare in South Korea, and is part of the group's eldest line. Trivia: She is a former contestant of the JTBC audition program "R U Next?". She has expressed a bold ambition to be recognized for the group's unique identity rather than any other labels.

Real Name: Shin Hyewon Nationality: South Korea Date of Birth: October 5, 2005 Position: Vocalist Personality: She is cautious and calm, but possesses a reversal charm with her intense immersion on stage. Characteristics: She is a 're-debut' member who previously active as a child star and in the kids' idol group 'Rich Girl' under the stage name 'Lael.' She boasts a unique vocal color and stable singing ability. Trivia: A former Belift Lab trainee, she has a notable history of participating in "R U Next?" alongside Jo Hyejin and Guk Chorok.

Real Name: Jo Hyejin Nationality: South Korea Date of Birth: October 5, 2005 Position: Leader, Main Dancer, Vocalist Personality: An inclusive type who looks after the members reliably like a father figure (MBTI: ENFJ). Characteristics: The final winner of the KBS audition program "The Tantara" and a highly skilled dancer who appeared on Mnet's "Street Dance Girls Fighter 2." Trivia: A graduate of the Practical Dance department at Hanlim Multi Art School, she received high praise from Park Jin-young, who called her "so special."

Real Name: Kawasaki Yuu Nationality: Japan Date of Birth: August 21, 2008 Position: Vocalist, Dancer, Rapper Personality: Contrary to her cute appearance, she possesses strong grit and never gives up in any moment. Characteristics: After appearing on SBS's "Universe Ticket," she participated in KBS's "The Tantara" and placed 3rd overall, proving her solid skill set. She is an ace who handles singing, dancing, and rapping. Trivia: She built global fandom recognition early on by going through two survival programs before her debut.

Real Name: Hsieh Chia-hsuan Nationality: Taiwan Date of Birth: February 10, 2009 Position: Main Dancer Personality: Like her name, she is baby-like and cheerful, but shows a powerful reversal charm on stage. Characteristics: Along with leader Jo Hyejin, she serves as a powerful performance pillar of the team. She holds a very high center proportion in hip-hop-based stages and is characterized by her eye-catching dance lines. Trivia: She first made her face known as a unit member for the pre-debut single "HUNGRY (Side A)" released before the official debut.

Real Name: Achiraya Kawinwit Nationality: Thailand Date of Birth: August 18, 2009 Position: Vocalist Personality: She possesses a creative and artistic sense and prefers a free-spirited vibe. Characteristics: She is the third Thai member from JYP Entertainment, following in the footsteps of Nichkhun and BamBam. Her charming voice tone adds an exotic and trendy feel to their songs. Trivia: A former Abyss Company trainee, she has experience performing on stage at senior artist BamBam's concert in Thailand before her debut.

Real Name: Takashima Kirara Nationality: Japan Date of Birth: December 17, 2010 (The youngest of the team) Position: Vocalist Personality: She is loved by the older members for her purity and bubbly liveliness. Characteristics: She was revealed last as the team's final hidden card to complete the 7-member lineup. She is the member who best brings out the kitschy charm of OURBIRTHDAY's proprietary genre, 'Whip-Hop.' Trivia: Despite her young age, she is considered a promising star for individual fan-cams due to her excellent facial expressions on stage.