F23

F23 or F-23 may refer to:

• Fluorine-23 (²³F), an isotope of fluorine
• Funk F-23, an American agricultural aircraft
• Getrag F23 transmission, an Italian 5-speed manual transmission
• Hirth F-23, an aircraft engine
• HMS Kanimbla (F23), a passenger ship requisitioned for the Royal Navy
• HMS Teazer (F23), a T-class destroyer of the Royal Navy
• Northrop F-23, an American fighter aircraft design, developed from the YF-23