IU celebrated her 21st birthday.

Today, singer IU posted on her Facebook, "Big celebration for IU's 21st birthday! Congratulations! Please congratulate her big too!!!"

Internet users who saw this commented, "I'm enjoying your drama. Happy birthday, Soon Shin!," "Congratulations. I'm excited for your new album," "I love you IU," and "Happy birthday!"

On May 6, IU had posted on her fan website, "I was planning to leave a post on my birthday but I was so thankful for the birthday presents I received 10 days early so I suddenly decided to leave this post. I have a lot to say but I'll wait until the 16th."

IU is currently playing the role of Lee Soon Shin for KBS 2TV drama "You're the Best, Lee Soon Shin."

Photo Credit: IU Facebook