X1 (엑스원) is an 11-member project boy group under Swing Entertainment and Stone Music Entertainment. They were formed through Mnet's competition reality show Produce X 101 and debuted on August 27, 2019 with their first mini album [albumartist=X1]Quantum Leap.

They will be active for five years on a special contract, where the first semester is intended for them to focus solely on the group, and in the second half they will be able to do work within their own companies, such as solo debut, a member of a new group or returning to work with a former group. They will disband sometime in 2024. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.