CL2 may refer to: Chlorine gas, Cl2 the Clausen function of order 2, Cl2 the Clifford algebra on , CAS latency 2, a rating of computer memory Google Calendar, a time-management web application (from a URL fragment used in early versions) Only Built 4 Cuban Linx II, a musical album by American hip-hop artist Raekwon Class 2 rated cables, in the National Electrical Code LPHN2, a human gene that encodes the Latrophilin-2 protein