FF, ff, or fF may refer to:

  • ‹ff›, a Latin alphabet digraph; it is used in English orthography to represent the same sound as single ‹f›, /f/
  • ff, a typographic ligature
  • 255 (number) (hexadecimal: FF16), the natural number following 254 and preceding 256
  • Femtofarad (fF), 1×10−15 farads or units of capacitance
  • Fula language (ISO 639-1 code ff), a language of West Africa
  • Mukti Bahini (Freedom Fighters), the armed organizations who fought against the Pakistan Army during the Bangladesh Liberation War
  • Tower Air (IATA code: FF), a certificated FAR 121 schedule and charter U.S. airline that operated from 1983 until 2000
  • Fianna Fáil, political party in the Republic of Ireland and Northern Ireland

Read more about FF:  Science, Technology, Computing and Electronics, Other