N5 or N-5 may refer to:

• N₅, the minimal non-modular and non-distributive lattice in mathematical order theory
• N5, abbreviation for the 5 nanometer semiconductor technology process node

• N°5, a shortening for Number Five, see Number Five (disambiguation)
• ASEA N-5, rolling stock used on the SEPTA Norristown High Speed Line
• LNER Class N5, a class of British steam locomotives
• London Buses route N5
• Nexus 5, an Android smartphone
• N5, a postcode district in the N postcode area, North London, England
• SP&S Class N-5, a steam locomotives class, used by the Spokane, Portland and Seattle Railway
• USS N-5 (SS-57), a 1917 N-class coastal defense submarine of the United States Navy
• The first level in the Japanese-Language Proficiency Test
• "N5" (song), by Lali, 2022

• N05 (disambiguation)
• Pentazenium (N₅⁺), a pentanitrogen cation in chemistry
• pentazolium cation (N₅⁺), a cation that is made up of five nitrogen atoms, in chemistry.
• pentazolate anion (N₅⁻), an anion that is made up of five nitrogen atoms, in chemistry
• 5N (disambiguation)