ETX may refer to:
- ETX (form factor), Embedded Technology eXtended computer-on-module specification
- Meade ETX telescope, popular line of compact Maksutov-Cassegrain telescopes made by Meade Instruments Corporation
- End-of-text character, character code within the C0 and C1 control codes range
- Expected Transmission Count, network routing metric
ETX, standing for Embedded Technology eXtended, is an integrated and compact computer-on-module (COM) form factor, which can be used in a design application much like an integrated circuit component. Each ETX COM integrates core CPU and memory functionality, the common I/O of a PC/AT (serial, parallel, etc.), USB, audio, graphics, and Ethernet. All I/O signals as well as a full implementation of ISA and PCI buses are mapped to four high-density, low-profile connectors on the bottom side of the module.
ETX boards are available with AMD Geode, VIA, Intel Atom, Pentium, Celeron and Core Duo processors.
XTX offers a 75% pin-compatible upgrade path to ETX standard. XTX drops the ISA bus and adds PCI-Express, SATA, and LPC.
COM Express was released in 2005 from PICMG.