I3, I-3 or i3 may refer to:
Science and technology Core i3, a microprocessor line from Intel i3 (window manager), a tiling window manager Triiodide (I3−), an anion composed of 3 iodide atoms Intermud-3, an InterMUD network method between MUDs Axiom I3, a large cardinal axiom in rank-into-rank set theory
Transport Interstate 3, a former proposed Interstate Highway in the U.S. states of Georgia and Tennessee BMW i3 (hatchback), an electric car by BMW Inline-triple engine, an internal combustion engine with three cylinders in a straight line LB&SCR I3 class, a British LB&SCR locomotive Circuito Norte (I–3), a Cuban highway going along the northern coast of the island Vía Blanca (I–3), motorway from Havana to Varadero Autopista Sur (I–3), motorway in Varadero Autopista Havana–Mariel (I–3), motorway from Havana to Mariel
Military , a Type J1 submarine of the Imperial Japanese Navy i3 fighter, a conceptual Japanese jet fighter proposed in 2010 Mikoyan-Gurevich I-3, a heavy interceptor prototype fighter of the 1950s Polikarpov I-3, a 1928 Soviet biplane fighter
See also
3I (disambiguation)