"20 years ago today I won American Idol and it forever changed the course of my life," Clarkson posted the news on her Instagram.
"That moment was the one that gave me so many possibilities and access to artistic collaborations that I will be thankful for throughout my life.
The friendships and family I've made over the last 20 years of the fields of television and music are priceless to me.
Since that time, Clarkson scored many hits which comprise "Miss Independent," "Breakaway," "Since U Been Gone," "Because of You" and "Behind These Hazel Eyes," as well as many others.
"Thank you very much to everyone who was a voter 20 years ago! Thank you! Thank you! Thank you!
‘American Idol’ OG Winner Kelly Clarkson
I'm sure that all of you are blessed with people in your life that make you smile and hope, as well as happiness.
If you don't believe you've got that, continue searching, because I'll assure that they're seeking the same thing," she concluded.