In

IN, out or in may refer to:

Places

Independent Network, a UK-based political association
Indiana Northeastern Railroad (Association of American Railroads reporting mark)
Indian Navy, a part of the India military
Infantry, the branch of a military force that fights on foot
IN Groupe, the producer of French official documents
MAT Macedonian Airlines (IATA designator IN)
Nam Air (IATA designator IN)
Office of Intelligence and Counterintelligence, sometimes abbreviated IN

.in, the internet top-level domain of India
Inch (in), a unit of length
Indium, symbol In, a chemical element
Intelligent Network, a telecommunication network standard
Intra-nasal (insufflation), a method of administrating some medications and vaccines
Integrase, a retroviral enzyme

In (album), by the Outsiders, 1967
In (Korean name), a family name and an element in given names
"In", an episode of Minder
Imperishable Night, the eighth official game in the Japanese Touhou series
Indonesian language (former ISO 639-1 language code; "id" used since November 3, 1989)
In Nomine, a title given to any of numerous short pieces of English polyphonic instrumental or vocal music during the 16th and 17th centuries
I.N (born Yang Jeong-in, 2001), South Korean singer and member of boy band Stray Kids