1/12

1/12 may refer to:
 * January 12 (month-day date notation)
 * December 1 (day-month date notation)
 * January 12 AD (month-year date notation)
 * 1 AD December (year-month date notation)
 * 1st Battalion, 12th Marines, an artillery battalion of the United States Marine Corps
 * 1/12 or 1:12 scale
 * Maximum slope of a wheelchair ramp under regulations in several countries