Current ROBUX logo. ROBUX visualized as a physical currency, also seen on Xbox. ROBUX (singular ROBUK, plural ROBUX) or ROBUCK, stylized as R$, is the sole currency on ROBLOX. Introduced on May 14, 2007, ROBUX is known as ROBLOX's primary currency by the community and staff; all ROBLOX-created items within the catalog are sold in ROBUX.