IoT may refer to:
- Internet of things, connecting everyday objects to the internet
- Illuminates of Thanateros, an international magical organization
- Inductive output tube, a variety of vacuum tube
- Institute of Transportation, an agency in Taiwan
- Interoperability testing, to determine the interoperability of a product
- Input-Output Transfer, instructions for computers as in the PDP-8
- Completed operations indicator, in Belgian railway signalling
