XN may refer to:

Xnet (former eXgae) is a non-profit activist platform that develops and promotes alternative models for cultural dissemination and royalty management and work in different fields related to digital rights, networked democracy and freedom of expression.

XNU is the computer operating system kernel developed at Apple Inc. since December 1996 for use in the macOS operating system and released as free and open-source software as part of the Darwin operating system.

The XNOR gate (sometimes ENOR, EXNOR or NXOR and pronounced as Exclusive NOR) is a digital logic gate whose function is the logical complement of the exclusive OR (XOR) gate.

XnView is an image organizer and general-purpose file manager used for viewing, converting, organizing and editing raster images, as well as general purpose file management.

"Xnoybis" is a song by the industrial metal band Godflesh, taken from the album Selfless (1994). It was released in 1995 through Earache Records as a CD, and was also distributed as a promotional to radio stations.

Xnews is a freeware Usenet newsreader created by Luu Tran. It is written in Delphi, and it is 100% GNKSA 2.0 compliant.

GNU Xnee is a suite of programs that can record, replay and distribute user actions under the X11 environment.

In number theory Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive integers a, b, and c satisfy the equation an + bn = cn for any integer value of n greater than 2. The cases n = 1 and n = 2 have been known to have infinitely many solutions since antiquity.This theorem was first conjectured by Pierre de Fermat in 1637 in the margin of a copy of Arithmetica where he claimed he had a proof that was too large to fit in the margin.