TDI

TDI may refer to:

Science and technology

 * Tolerable daily intake, in toxicology
 * Toluene diisocyanate, an organic chemical
 * Time delay and integration, timing synchronization in an image sensor
 * Tissue Doppler imaging, a medical ultrasound technology
 * Tabbed document interface, a type of graphical user interface
 * Total dual integrality, a property of matrices in mathematical optimization
 * Transport Driver Interface, used by NT series Windows to abstract level 7 APIs into a common protocol for the Transport Protocol layer
 * Trophic Diatom Index, water quality and ecological status; see Sattal
 * TDI (engine) (turbocharged direct injection), a diesel engine design used in cars and light vans made by Volkswagen Group

Organizations

 * Technical Diving International, a technical diving organization
 * Telecommunications for the Deaf, Inc., a nonprofit organization promoting telecommunications devices for the deaf
 * Texas Department of Insurance
 * The Dartmouth Institute for Health Policy and Clinical Practice, a subsidiary of Dartmouth College
 * Transportation Displays, Inc., a unit of Outfront Media

Entertainment

 * Total Drama Island, an animated reality series
 * Total Drama Island (2023), the 2023 reboot with the same name.
 * Tangerine Dream Independent, the record label belonging to Edgar Froese