UDTT

UDTT (우당탕탕 소녀단) is a 5-member South Korean girl group under SW Entertainment. The group consists of Risako, Han Chaehee, Koo Hanna, Lu Yuting, and Kwon Yejin. Jung Sena left the group on March 26, 2025. They released their first pre-debut single titled “𝐑𝐄𝐓𝐑𝐘” on December 11, 2024. They officially debuted on April 29, 2025, with their first single album, School Rush.

UDTT members height, age

Click on a member's name to scroll to their profile

Member	Height	Age
Risako	161 cm	29 years
Han Chaehee	168 cm	24 years
Koo Hanna	167 cm	22 years
Lu Yuting	174 cm	21 years
Kwon Yejin	—	20 years

Former members (1)

Member	Height	Age
Jung Sena	—	20 years

Debut Date: April 29, 2025
Group Name Meaning: UDTT Is short for Uddang Tangtang Girls.
Official Greeting: "(two, three) Oops! Hello, We are UDTT!"

Official links

Group Stats

Average height: 167.5 cm
Tallest: 174 cm · Lu Yuting
Shortest: 161 cm · Risako
Average age: 23.2 years
Oldest: 29 years · Risako
Youngest: 20 years · Kwon Yejin

Members

Risako

Stage Name: Risako (리사코)
Birth Name: Arai Risako (新井理沙子)
Position(s): Leader, Vocalist, Dancer
Birthday: June 7, 1997
Age: 29 years
Chinese Zodiac Sign: Ox
Height: 161 cm (5'3.5″)
MBTI Type: ENFJ
Nationality: Japanese
Representative Color: Blue
Representative Emoji: 🐨

Facts

Risako was revealed as the first member on Nov 24, 2024.
Her hobbies are drawing and visiting Mangwon Market.
Her specialties are dancing, Korean, and vocal mimicry.
She is the smallest member.
She competed on Girls Planet 999, eliminated in episode 8.
She trained under iMe Korea (2022-2023) and Biscuit Entertainment (2021).
Her motto: “Never get tired of her attractive dancing, Arai Risako!”
She speaks Japanese and Korean.
She can play piano.
She worked as a backup dancer for major Japanese artists since childhood.
Her nickname is RIRI.
Her favorite number is six.
Her favorite colors are light pink, purple, and sky blue.
Her favorite season is spring.
Her favorite songs are “Lion Heart” (Girls’ Generation), “Biidama” (Ai Otsuka), and “Actually, No” (Yu Dongran).

Han Chaehee

Stage Name: Han Chaehee (한채희)
Birth Name: Han Chae Hee (한채희)
Position(s): Sub Vocalist
Birthday: November 13, 2001
Age: 24 years
Zodiac Sign: Scorpio
Chinese Zodiac Sign: Snake
Height: 168 cm (5'6″)
Weight: 47 kg (103 lbs)
Blood Type: A
MBTI Type: INFP
Nationality: Korean
Representative Color: Purple
Representative Emoji: 🐱

Facts

She was revealed as the fifth member on Nov 28, 2024.
She was a member of pre-debut group G.I.G.
She trained under CUP Entertainment (2021-2022).
She won the 2016 Youth Dance Competition and received cultural arts festival awards.
Her nickname is Angel Cat.
Her favorite number is seven.
Though positioned as a vocalist, she considers herself a good dancer.
Her favorite colors are pink and purple.
Her favorite season is spring.
She describes herself as “I’m stronger than you think.”
Her charm points are her eyes and her lovely personality.
She recommends “I Don’t Think That I Like Her” (Charlie Puth), “Wolves” (Selena Gomez), and “Psycho” (Red Velvet).
She has never ridden a roller coaster but wants to with members.

Koo Hanna

Stage Name: Koo Hanna (구한나)
Birth Name: Koo Hyun Kyoung (구현경)
Position(s): Main Vocalist, Dancer
Birthday: January 20, 2004
Age: 22 years
Zodiac Sign: Aquarius
Chinese Zodiac Sign: Goat
Height: 167 cm (5'5.5″)
Blood Type: A
MBTI Type: ESTJ & ISTJ
Nationality: Korean
Representative Color: Pink
Representative Emoji: 🐰

Facts

She was revealed as the second member on Nov 25, 2024.
She studied at STAGE631 Academy and Flat9 Academy.
Her motto: “My youth is blood, sweat, and tears.”
She trained under iMe Korea, PocketDol Studio (2021), BEATS Entertainment (2022-2023), and Biscuit Entertainment (2021).
She competed on My Teenage Girl, eliminated in episode 3.
Her hashtags are #refreshing, #smilingangel, and #giantbaby.
She was a backup dancer at the 2019 H.O.T. concert.
She appeared in T-ara Jiyeon’s “Take a Hike” choreography video.
Her nicknames include Tokkeng-i and Chaotic.
Her favorite number is nine.
Her favorite colors are pink and ivory.
Her favorite season is spring.
Her charm point is being cute yet sexy.
Her favorite body parts are her nose, lips, and sparkly eyes.
She recommends “Deja Vu” (Olivia Rodrigo).

Lu Yuting

Stage Name: Lu Yuting (우정)
Birth Name: Lu Yu Ting (陆雨婷)
Korean Name: Yuk Woo Jeong (육우정)
English Name: Jessica Lu
Position(s): N/A
Birthday: February 17, 2005
Age: 21 years
Zodiac Sign: Aquarius
Chinese Zodiac Sign: Rooster
Height: 174 cm (5'8.5″)
MBTI Type: ENTJ
Nationality: Chinese

Facts

She is from Beijing, China.
She plays piano, guitar, and drums.
She trained under International Star Family (2019-2021), PI Corporation (2024-2025), GOLDDUST Entertainment (2023-2024), and Moai Entertainment (2025, unsigned).
She was in IS GIRL (2019-2021) and pre-debut groups BEWAVE, I.MET.U (2024-2025), and E11iVYN (2025).
She debuted solo on Jul 17, 2022, with “仲夏夜梦” under her real name.
She competed on Chuang Asia Thailand (ranked 18th) and Time Turner (ranked 3rd, joined I.MET.U but left before debut).
She is a big BLACKPINK fan.
Yuting’s role model is BLACKPINK’s Jisoo.
Her favorite song is “Don’t Know What to Do” (BLACKPINK).
Her favorite color is pink.
She loves Harry Potter movies.
She is friends with tripleS’s Xinyu, CSR’s Duna, and others.
She studied Music Performance at Berklee College of Music.
She trained for about 6-7 years.
She was revealed as a new member on Apr 29, 2025.

Kwon Yejin

Stage Name: Kwon Yejin (권예진)
Birth Name: Kwon Ye Jin (권예진)
Position(s): Sub Vocalist, Maknae
Birthday: June 26, 2006
Age: 20 years
Zodiac Sign: Cancer
Chinese Zodiac Sign: Dog
MBTI Type: ENTP
Nationality: Korean
Representative Color: Green
Representative Emoji: 🐶

Facts

She was revealed as the third member on Nov 26, 2024.
Her nickname is Geuroppi.
She studied at Lila Art High School.
She dislikes bugs.
Her charm points are her dimples.
She competed on Universe Ticket, eliminated in episode 4 (rank #72).
She is the best artist among members.
Her nickname is “Frog with big eyes.”
Her favorite number is three.
Her favorite color is mint.
Her favorite season is summer.
She describes herself as “chihuahua.”
Her charm points are the moles under her eyes.
She recommends “This is What Winter Feels Like” (JVKE), “Sea” (BTS), and “Roar” (Katy Perry).
Members say she is half F and half T in personality.

Former member

Jung Sena

Stage Name: Jung Sena (정세나)
Birth Name: Jung Seung Ha (정승하)
Position(s): Main Rapper, Sub Vocalist, Maknae
Birthday: October 22, 2006
Zodiac Sign: Libra
Chinese Zodiac Sign: Dog
MBTI Type: INFJ
Nationality: Korean
Representative Color: Yellow
Representative Emoji: 🐯

Facts

She was revealed as the fourth member on Nov 27, 2024.
She graduated from a dance department, winning the 2021 “Dance and Opera” award and SAC Competition prize.
She studied at Hanlim Arts School.
Members say Sena isn’t “J” because she doesn’t plan much.
Her nickname is MC Sena.
Her favorite number is seven.
Her favorite colors are pink and pale yellow.
She often gives nicknames to members.
She dislikes orange; she once disliked yellow but found it suits her best.
Her favorite season is fall.
She describes herself as Baby Cat, Maknae, Cat, and Baby.
Her charm point is her thick lips.
Her favorite songs are “Sorry Not Sorry” (Demi Lovato), “I’ll Be There,” and “This Love” (Maroon 5).
She once dreamed she lived 30 years as a cat.
Her favorite animals are cats.
Jung Sena left the group on Mar 26, 2025, for personal reasons.