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›, a typographic ligature
- 255 (number) (hexadecimal: FF), the natural number following 254 and preceding 256
- Femtofarad (fF), 1×10 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
- False flag, a diversionary or propaganda tactic
- Faraday Future, a car company
Usage examples of "ff".
The punishments of Dirce and the Danaides are cited in I Clement vi, 1 ff.
Although some are wary of using II Timothy and the other pastoral epistles as evidence, even critical scholars admit that the letter probably contains authentic Pauline reminiscences in verses such as I:8 ff., I:15 ff.
Chances are that his widow would be living as she is now ff. tine had come that close to the edge.