Resolution 8 of the 12th CGPM (1964)

SI prefixes femto and atto

The 12th Conférence Générale des Poids et Mesures (CGPM),

decides to add to the list of prefixes for the formation of names of multiples and submultiples of units, adopted by the 11th CGPM, Resolution 12, paragraph 3, the following two new prefixes:

Multiplying factor Prefix Symbol
10–15 femto f
10–18 atto a

DOI : 10.59161/CGPM1964RES8E

The reader should note that the official version of this Resolution is the French text


New prefixes were added by the 15th CGPM in 1975 (Resolution 10).

CGPM logo

Menu Display