SMX

SMX may refer to:

As an abbreviation:
 * SMX (operating system), a Unix-like simulator on SPARC, the "SunOS/Solaris MINIX"
 * Standard Musical Expression, a representation of simple music in ASCII that was used in some DOS software such as QBasic
 * SMX Convention Center (company), an events venue management company in the Philippines
 * SMX Convention Center Manila, Pasay, Philippines
 * Sulfamethoxazole, an antibiotic
 * Honda S-MX, a minivan
 * Spatial multiplexing, MIMO wireless transmission technique
 * Singapore Mercantile Exchange
 * SmX RNA and SmY RNA, ribonucleic acids in nematode worms
 * S.M.X., director of Revelation at the 1999 New York Underground Film Festival
 * StepManiaX, a rhythm game by Step Revolution

As a code:
 * Santa Maria Public Airport, in California, US, IATA code
 * C.A.I. First, regional Italian airline, ICAO airline code
 * SMTC Corporation, Canada, TSX/Toronto ticker code
 * Sanmenxia city in Henan, China, governmental code SMX
 * Sendmail X, now MeTA1, mail server coded smX
 * Special Mobile Machine—Exempt, prefix SMX, on vehicle registration plates of Colorado