IID (disambiguation)

IID may refer to:


 * Interface Identifier, the last 64-bits of an IPv6 address
 * Internet identity, a social identity used by Internet users
 * Internet Identity, an Internet security company
 * Ignition interlock device, a breathalyzer connected to a vehicle's engine
 * Independent and identically distributed random variables in probability theory
 * Interaural intensity difference in determining the location of a sound
 * Internal Investigations Division (in law enforcement)
 * IRIX Interactive Desktop, software for interacting with a computer running the IRIX operating system
 * Iterative and Incremental Development in software development
 * A COM Interface ID
 * Invoke Image Display an Integrating the Healthcare Enterprise (IHE) Integration Profile
 * Imperial Irrigation District
 * IID (Imperial Institute of Design), a design school in Monteswar, West Bengal, India